/* * wiringPi: * Arduino look-a-like Wiring library for the Raspberry Pi * Copyright (c) 2012-2017 Gordon Henderson * Additional code for pwmSetClock by Chris Hall * * Thanks to code samples from Gert Jan van Loo and the * BCM2835 ARM Peripherals manual, however it's missing * the clock section /grr/mutter/ *********************************************************************** * This file is part of wiringPi: * https://projects.drogon.net/raspberry-pi/wiringpi/ * * wiringPi is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * wiringPi is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with wiringPi. * If not, see . *********************************************************************** */ // Revisions: // 19 Jul 2012: // Moved to the LGPL // Added an abstraction layer to the main routines to save a tiny // bit of run-time and make the clode a little cleaner (if a little // larger) // Added waitForInterrupt code // Added piHiPri code // // 9 Jul 2012: // Added in support to use the /sys/class/gpio interface. // 2 Jul 2012: // Fixed a few more bugs to do with range-checking when in GPIO mode. // 11 Jun 2012: // Fixed some typos. // Added c++ support for the .h file // Added a new function to allow for using my "pin" numbers, or native // GPIO pin numbers. // Removed my busy-loop delay and replaced it with a call to delayMicroseconds // // 02 May 2012: // Added in the 2 UART pins // Change maxPins to numPins to more accurately reflect purpose #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "softPwm.h" #include "softTone.h" #include "wiringPi.h" #include "../version.h" // Environment Variables #define ENV_DEBUG "WIRINGPI_DEBUG" #define ENV_CODES "WIRINGPI_CODES" #define ENV_GPIOMEM "WIRINGPI_GPIOMEM" // Extend wiringPi with other pin-based devices and keep track of // them in this structure struct wiringPiNodeStruct *wiringPiNodes = NULL ; // BCM Magic #define BCM_PASSWORD 0x5A000000 // The BCM2835 has 54 GPIO pins. // BCM2835 data sheet, Page 90 onwards. // There are 6 control registers, each control the functions of a block // of 10 pins. // Each control register has 10 sets of 3 bits per GPIO pin - the ALT values // // 000 = GPIO Pin X is an input // 001 = GPIO Pin X is an output // 100 = GPIO Pin X takes alternate function 0 // 101 = GPIO Pin X takes alternate function 1 // 110 = GPIO Pin X takes alternate function 2 // 111 = GPIO Pin X takes alternate function 3 // 011 = GPIO Pin X takes alternate function 4 // 010 = GPIO Pin X takes alternate function 5 // // So the 3 bits for port X are: // X / 10 + ((X % 10) * 3) // Port function select bits #define FSEL_INPT 0b000 #define FSEL_OUTP 0b001 #define FSEL_ALT0 0b100 #define FSEL_ALT1 0b101 #define FSEL_ALT2 0b110 #define FSEL_ALT3 0b111 #define FSEL_ALT4 0b011 #define FSEL_ALT5 0b010 // Access from ARM Running Linux // Taken from Gert/Doms code. Some of this is not in the manual // that I can find )-: // // Updates in September 2015 - all now static variables (and apologies for the caps) // due to the Pi v2, v3, etc. and the new /dev/gpiomem interface static volatile unsigned int GPIO_PADS ; static volatile unsigned int GPIO_CLOCK_BASE ; static volatile unsigned int GPIO_BASE ; static volatile unsigned int GPIO_TIMER ; static volatile unsigned int GPIO_PWM ; #define PAGE_SIZE (4*1024) #define BLOCK_SIZE (4*1024) // PWM // Word offsets into the PWM control region #define PWM_CONTROL 0 #define PWM_STATUS 1 #define PWM0_RANGE 4 #define PWM0_DATA 5 #define PWM1_RANGE 8 #define PWM1_DATA 9 // Clock regsiter offsets #define PWMCLK_CNTL 40 #define PWMCLK_DIV 41 #define PWM0_MS_MODE 0x0080 // Run in MS mode #define PWM0_USEFIFO 0x0020 // Data from FIFO #define PWM0_REVPOLAR 0x0010 // Reverse polarity #define PWM0_OFFSTATE 0x0008 // Ouput Off state #define PWM0_REPEATFF 0x0004 // Repeat last value if FIFO empty #define PWM0_SERIAL 0x0002 // Run in serial mode #define PWM0_ENABLE 0x0001 // Channel Enable #define PWM1_MS_MODE 0x8000 // Run in MS mode #define PWM1_USEFIFO 0x2000 // Data from FIFO #define PWM1_REVPOLAR 0x1000 // Reverse polarity #define PWM1_OFFSTATE 0x0800 // Ouput Off state #define PWM1_REPEATFF 0x0400 // Repeat last value if FIFO empty #define PWM1_SERIAL 0x0200 // Run in serial mode #define PWM1_ENABLE 0x0100 // Channel Enable // Timer // Word offsets #define TIMER_LOAD (0x400 >> 2) #define TIMER_VALUE (0x404 >> 2) #define TIMER_CONTROL (0x408 >> 2) #define TIMER_IRQ_CLR (0x40C >> 2) #define TIMER_IRQ_RAW (0x410 >> 2) #define TIMER_IRQ_MASK (0x414 >> 2) #define TIMER_RELOAD (0x418 >> 2) #define TIMER_PRE_DIV (0x41C >> 2) #define TIMER_COUNTER (0x420 >> 2) // Locals to hold pointers to the hardware static volatile uint32_t *gpio ; static volatile uint32_t *pwm ; static volatile uint32_t *clk ; static volatile uint32_t *pads ; #ifdef USE_TIMER static volatile uint32_t *timer ; static volatile uint32_t *timerIrqRaw ; #endif // Data for use with the boardId functions. // The order of entries here to correspond with the PI_MODEL_X // and PI_VERSION_X defines in wiringPi.h // Only intended for the gpio command - use at your own risk! // piGpioBase: // The base address of the GPIO memory mapped hardware IO #define GPIO_PERI_BASE_OLD 0x20000000 #define GPIO_PERI_BASE_NEW 0x3F000000 static volatile unsigned int piGpioBase = 0 ; const char *piModelNames [16] = { "Model A", // 0 "Model B", // 1 "Model A+", // 2 "Model B+", // 3 "Pi 2", // 4 "Alpha", // 5 "CM", // 6 "Unknown07", // 07 "Pi 3", // 08 "Pi Zero", // 09 "CM3", // 10 "Unknown11", // 11 "Pi Zero-W", // 12 "Unknown13", // 13 "Unknown14", // 14 "Unknown15", // 15 } ; const char *piRevisionNames [16] = { "00", "01", "02", "03", "04", "05", "06", "07", "08", "09", "10", "11", "12", "13", "14", "15", } ; const char *piMakerNames [16] = { "Sony", // 0 "Egoman", // 1 "Embest", // 2 "Unknown", // 3 "Embest", // 4 "Unknown05", // 5 "Unknown06", // 6 "Unknown07", // 7 "Unknown08", // 8 "Unknown09", // 9 "Unknown10", // 10 "Unknown11", // 11 "Unknown12", // 12 "Unknown13", // 13 "Unknown14", // 14 "Unknown15", // 15 } ; const int piMemorySize [8] = { 256, // 0 512, // 1 1024, // 2 0, // 3 0, // 4 0, // 5 0, // 6 0, // 7 } ; // Time for easy calculations static uint64_t epochMilli, epochMicro ; // Misc static int wiringPiMode = WPI_MODE_UNINITIALISED ; static volatile int pinPass = -1 ; static pthread_mutex_t pinMutex ; // Debugging & Return codes int wiringPiDebug = FALSE ; int wiringPiReturnCodes = FALSE ; // Use /dev/gpiomem ? int wiringPiTryGpioMem = FALSE ; // sysFds: // Map a file descriptor from the /sys/class/gpio/gpioX/value static int sysFds [64] = { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, } ; // ISR Data static void (*isrFunctions [64])(void) ; // Doing it the Arduino way with lookup tables... // Yes, it's probably more innefficient than all the bit-twidling, but it // does tend to make it all a bit clearer. At least to me! // pinToGpio: // Take a Wiring pin (0 through X) and re-map it to the BCM_GPIO pin // Cope for 3 different board revisions here. static int *pinToGpio ; // Revision 1, 1.1: static int pinToGpioR1 [64] = { 17, 18, 21, 22, 23, 24, 25, 4, // From the Original Wiki - GPIO 0 through 7: wpi 0 - 7 0, 1, // I2C - SDA1, SCL1 wpi 8 - 9 8, 7, // SPI - CE1, CE0 wpi 10 - 11 10, 9, 11, // SPI - MOSI, MISO, SCLK wpi 12 - 14 14, 15, // UART - Tx, Rx wpi 15 - 16 // Padding: -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // ... 31 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // ... 47 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // ... 63 } ; // Revision 2: static int pinToGpioR2 [64] = { 17, 18, 27, 22, 23, 24, 25, 4, // From the Original Wiki - GPIO 0 through 7: wpi 0 - 7 2, 3, // I2C - SDA0, SCL0 wpi 8 - 9 8, 7, // SPI - CE1, CE0 wpi 10 - 11 10, 9, 11, // SPI - MOSI, MISO, SCLK wpi 12 - 14 14, 15, // UART - Tx, Rx wpi 15 - 16 28, 29, 30, 31, // Rev 2: New GPIOs 8 though 11 wpi 17 - 20 5, 6, 13, 19, 26, // B+ wpi 21, 22, 23, 24, 25 12, 16, 20, 21, // B+ wpi 26, 27, 28, 29 0, 1, // B+ wpi 30, 31 // Padding: -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // ... 47 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // ... 63 } ; // physToGpio: // Take a physical pin (1 through 26) and re-map it to the BCM_GPIO pin // Cope for 2 different board revisions here. // Also add in the P5 connector, so the P5 pins are 3,4,5,6, so 53,54,55,56 static int *physToGpio ; static int physToGpioR1 [64] = { -1, // 0 -1, -1, // 1, 2 0, -1, 1, -1, 4, 14, -1, 15, 17, 18, 21, -1, 22, 23, -1, 24, 10, -1, 9, 25, 11, 8, -1, 7, // 25, 26 -1, -1, -1, -1, -1, // ... 31 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // ... 47 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // ... 63 } ; static int physToGpioR2 [64] = { -1, // 0 -1, -1, // 1, 2 2, -1, 3, -1, 4, 14, -1, 15, 17, 18, 27, -1, 22, 23, -1, 24, 10, -1, 9, 25, 11, 8, -1, 7, // 25, 26 // B+ 0, 1, 5, -1, 6, 12, 13, -1, 19, 16, 26, 20, -1, 21, // the P5 connector on the Rev 2 boards: -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 28, 29, 30, 31, -1, -1, -1, -1, -1, -1, -1, -1, } ; // gpioToGPFSEL: // Map a BCM_GPIO pin to it's Function Selection // control port. (GPFSEL 0-5) // Groups of 10 - 3 bits per Function - 30 bits per port static uint8_t gpioToGPFSEL [] = { 0,0,0,0,0,0,0,0,0,0, 1,1,1,1,1,1,1,1,1,1, 2,2,2,2,2,2,2,2,2,2, 3,3,3,3,3,3,3,3,3,3, 4,4,4,4,4,4,4,4,4,4, 5,5,5,5,5,5,5,5,5,5, } ; // gpioToShift // Define the shift up for the 3 bits per pin in each GPFSEL port static uint8_t gpioToShift [] = { 0,3,6,9,12,15,18,21,24,27, 0,3,6,9,12,15,18,21,24,27, 0,3,6,9,12,15,18,21,24,27, 0,3,6,9,12,15,18,21,24,27, 0,3,6,9,12,15,18,21,24,27, 0,3,6,9,12,15,18,21,24,27, } ; // gpioToGPSET: // (Word) offset to the GPIO Set registers for each GPIO pin static uint8_t gpioToGPSET [] = { 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, } ; // gpioToGPCLR: // (Word) offset to the GPIO Clear registers for each GPIO pin static uint8_t gpioToGPCLR [] = { 10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10, 11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11, } ; // gpioToGPLEV: // (Word) offset to the GPIO Input level registers for each GPIO pin static uint8_t gpioToGPLEV [] = { 13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13, 14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14, } ; #ifdef notYetReady // gpioToEDS // (Word) offset to the Event Detect Status static uint8_t gpioToEDS [] = { 16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16, 17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17, } ; // gpioToREN // (Word) offset to the Rising edge ENable register static uint8_t gpioToREN [] = { 19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, } ; // gpioToFEN // (Word) offset to the Falling edgde ENable register static uint8_t gpioToFEN [] = { 22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22,22, 23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23, } ; #endif // GPPUD: // GPIO Pin pull up/down register #define GPPUD 37 // gpioToPUDCLK // (Word) offset to the Pull Up Down Clock regsiter static uint8_t gpioToPUDCLK [] = { 38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38,38, 39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39,39, } ; // gpioToPwmALT // the ALT value to put a GPIO pin into PWM mode static uint8_t gpioToPwmALT [] = { 0, 0, 0, 0, 0, 0, 0, 0, // 0 -> 7 0, 0, 0, 0, FSEL_ALT0, FSEL_ALT0, 0, 0, // 8 -> 15 0, 0, FSEL_ALT5, FSEL_ALT5, 0, 0, 0, 0, // 16 -> 23 0, 0, 0, 0, 0, 0, 0, 0, // 24 -> 31 0, 0, 0, 0, 0, 0, 0, 0, // 32 -> 39 FSEL_ALT0, FSEL_ALT0, 0, 0, 0, FSEL_ALT0, 0, 0, // 40 -> 47 0, 0, 0, 0, 0, 0, 0, 0, // 48 -> 55 0, 0, 0, 0, 0, 0, 0, 0, // 56 -> 63 } ; // gpioToPwmPort // The port value to put a GPIO pin into PWM mode static uint8_t gpioToPwmPort [] = { 0, 0, 0, 0, 0, 0, 0, 0, // 0 -> 7 0, 0, 0, 0, PWM0_DATA, PWM1_DATA, 0, 0, // 8 -> 15 0, 0, PWM0_DATA, PWM1_DATA, 0, 0, 0, 0, // 16 -> 23 0, 0, 0, 0, 0, 0, 0, 0, // 24 -> 31 0, 0, 0, 0, 0, 0, 0, 0, // 32 -> 39 PWM0_DATA, PWM1_DATA, 0, 0, 0, PWM1_DATA, 0, 0, // 40 -> 47 0, 0, 0, 0, 0, 0, 0, 0, // 48 -> 55 0, 0, 0, 0, 0, 0, 0, 0, // 56 -> 63 } ; // gpioToGpClkALT: // ALT value to put a GPIO pin into GP Clock mode. // On the Pi we can really only use BCM_GPIO_4 and BCM_GPIO_21 // for clocks 0 and 1 respectively, however I'll include the full // list for completeness - maybe one day... #define GPIO_CLOCK_SOURCE 1 // gpioToGpClkALT0: static uint8_t gpioToGpClkALT0 [] = { 0, 0, 0, 0, FSEL_ALT0, FSEL_ALT0, FSEL_ALT0, 0, // 0 -> 7 0, 0, 0, 0, 0, 0, 0, 0, // 8 -> 15 0, 0, 0, 0, FSEL_ALT5, FSEL_ALT5, 0, 0, // 16 -> 23 0, 0, 0, 0, 0, 0, 0, 0, // 24 -> 31 FSEL_ALT0, 0, FSEL_ALT0, 0, 0, 0, 0, 0, // 32 -> 39 0, 0, FSEL_ALT0, FSEL_ALT0, FSEL_ALT0, 0, 0, 0, // 40 -> 47 0, 0, 0, 0, 0, 0, 0, 0, // 48 -> 55 0, 0, 0, 0, 0, 0, 0, 0, // 56 -> 63 } ; // gpioToClk: // (word) Offsets to the clock Control and Divisor register static uint8_t gpioToClkCon [] = { -1, -1, -1, -1, 28, 30, 32, -1, // 0 -> 7 -1, -1, -1, -1, -1, -1, -1, -1, // 8 -> 15 -1, -1, -1, -1, 28, 30, -1, -1, // 16 -> 23 -1, -1, -1, -1, -1, -1, -1, -1, // 24 -> 31 28, -1, 28, -1, -1, -1, -1, -1, // 32 -> 39 -1, -1, 28, 30, 28, -1, -1, -1, // 40 -> 47 -1, -1, -1, -1, -1, -1, -1, -1, // 48 -> 55 -1, -1, -1, -1, -1, -1, -1, -1, // 56 -> 63 } ; static uint8_t gpioToClkDiv [] = { -1, -1, -1, -1, 29, 31, 33, -1, // 0 -> 7 -1, -1, -1, -1, -1, -1, -1, -1, // 8 -> 15 -1, -1, -1, -1, 29, 31, -1, -1, // 16 -> 23 -1, -1, -1, -1, -1, -1, -1, -1, // 24 -> 31 29, -1, 29, -1, -1, -1, -1, -1, // 32 -> 39 -1, -1, 29, 31, 29, -1, -1, -1, // 40 -> 47 -1, -1, -1, -1, -1, -1, -1, -1, // 48 -> 55 -1, -1, -1, -1, -1, -1, -1, -1, // 56 -> 63 } ; /* * Functions ********************************************************************************* */ /* * wiringPiFailure: * Fail. Or not. ********************************************************************************* */ int wiringPiFailure (int fatal, const char *message, ...) { va_list argp ; char buffer [1024] ; if (!fatal && wiringPiReturnCodes) return -1 ; va_start (argp, message) ; vsnprintf (buffer, 1023, message, argp) ; va_end (argp) ; fprintf (stderr, "%s", buffer) ; exit (EXIT_FAILURE) ; return 0 ; } /* * piGpioLayout: * Return a number representing the hardware revision of the board. * This is not strictly the board revision but is used to check the * layout of the GPIO connector - and there are 2 types that we are * really interested in here. The very earliest Pi's and the * ones that came after that which switched some pins .... * * Revision 1 really means the early Model A and B's. * Revision 2 is everything else - it covers the B, B+ and CM. * ... and the Pi 2 - which is a B+ ++ ... * ... and the Pi 0 - which is an A+ ... * * The main difference between the revision 1 and 2 system that I use here * is the mapping of the GPIO pins. From revision 2, the Pi Foundation changed * 3 GPIO pins on the (original) 26-way header - BCM_GPIO 22 was dropped and * replaced with 27, and 0 + 1 - I2C bus 0 was changed to 2 + 3; I2C bus 1. * * Additionally, here we set the piModel2 flag too. This is again, nothing to * do with the actual model, but the major version numbers - the GPIO base * hardware address changed at model 2 and above (not the Zero though) * ********************************************************************************* */ static void piGpioLayoutOops (const char *why) { fprintf (stderr, "Oops: Unable to determine board revision from /proc/cpuinfo\n") ; fprintf (stderr, " -> %s\n", why) ; fprintf (stderr, " -> You'd best google the error to find out why.\n") ; //fprintf (stderr, " -> http://www.raspberrypi.org/phpBB3/viewtopic.php?p=184410#p184410\n") ; exit (EXIT_FAILURE) ; } int piGpioLayout (void) { FILE *cpuFd ; char line [120] ; char *c ; static int gpioLayout = -1 ; if (gpioLayout != -1) // No point checking twice return gpioLayout ; if ((cpuFd = fopen ("/proc/cpuinfo", "r")) == NULL) piGpioLayoutOops ("Unable to open /proc/cpuinfo") ; // Start by looking for the Architecture to make sure we're really running // on a Pi. I'm getting fed-up with people whinging at me because // they can't get it to work on weirdFruitPi boards... while (fgets (line, 120, cpuFd) != NULL) if (strncmp (line, "Hardware", 8) == 0) break ; if (strncmp (line, "Hardware", 8) != 0) piGpioLayoutOops ("No \"Hardware\" line") ; if (wiringPiDebug) printf ("piGpioLayout: Hardware: %s\n", line) ; // See if it's BCM2708 or BCM2709 or the new BCM2835. // OK. As of Kernel 4.8, we have BCM2835 only, regardless of model. // However I still want to check because it will trap the cheapskates and rip- // off merchants who want to use wiringPi on non-Raspberry Pi platforms - which // I do not support so don't email me your bleating whinges about anything // other than a genuine Raspberry Pi. if (! (strstr (line, "BCM2708") || strstr (line, "BCM2709") || strstr (line, "BCM2835"))) { fprintf (stderr, "Unable to determine hardware version. I see: %s,\n", line) ; fprintf (stderr, " - expecting BCM2708, BCM2709 or BCM2835.\n") ; fprintf (stderr, "If this is a genuine Raspberry Pi then please report this\n") ; fprintf (stderr, "to projects@drogon.net. If this is not a Raspberry Pi then you\n") ; fprintf (stderr, "are on your own as wiringPi is designed to support the\n") ; fprintf (stderr, "Raspberry Pi ONLY.\n") ; exit (EXIT_FAILURE) ; } // Right - we're Probably on a Raspberry Pi. Check the revision field for the real // hardware type // In-future, I ought to use the device tree as there are now Pi entries in // /proc/device-tree/ ... // but I'll leave that for the next revision. // Isolate the Revision line rewind (cpuFd) ; while (fgets (line, 120, cpuFd) != NULL) if (strncmp (line, "Revision", 8) == 0) break ; fclose (cpuFd) ; if (strncmp (line, "Revision", 8) != 0) piGpioLayoutOops ("No \"Revision\" line") ; // Chomp trailing CR/NL for (c = &line [strlen (line) - 1] ; (*c == '\n') || (*c == '\r') ; --c) *c = 0 ; if (wiringPiDebug) printf ("piGpioLayout: Revision string: %s\n", line) ; // Scan to the first character of the revision number for (c = line ; *c ; ++c) if (*c == ':') break ; if (*c != ':') piGpioLayoutOops ("Bogus \"Revision\" line (no colon)") ; // Chomp spaces ++c ; while (isspace (*c)) ++c ; if (!isxdigit (*c)) piGpioLayoutOops ("Bogus \"Revision\" line (no hex digit at start of revision)") ; // Make sure its long enough if (strlen (c) < 4) piGpioLayoutOops ("Bogus revision line (too small)") ; // Isolate last 4 characters: (in-case of overvolting or new encoding scheme) c = c + strlen (c) - 4 ; if (wiringPiDebug) printf ("piGpioLayout: last4Chars are: \"%s\"\n", c) ; if ( (strcmp (c, "0002") == 0) || (strcmp (c, "0003") == 0)) gpioLayout = 1 ; else gpioLayout = 2 ; // Covers everything else from the B revision 2 to the B+, the Pi v2, v3, zero and CM's. if (wiringPiDebug) printf ("piGpioLayoutOops: Returning revision: %d\n", gpioLayout) ; return gpioLayout ; } /* * piBoardRev: * Deprecated, but does the same as piGpioLayout ********************************************************************************* */ int piBoardRev (void) { return piGpioLayout () ; } /* * piBoardId: * Return the real details of the board we have. * * This is undocumented and really only intended for the GPIO command. * Use at your own risk! * * Seems there are some boards with 0000 in them (mistake in manufacture) * So the distinction between boards that I can see is: * * 0000 - Error * 0001 - Not used * * Original Pi boards: * 0002 - Model B, Rev 1, 256MB, Egoman * 0003 - Model B, Rev 1.1, 256MB, Egoman, Fuses/D14 removed. * * Newer Pi's with remapped GPIO: * 0004 - Model B, Rev 1.2, 256MB, Sony * 0005 - Model B, Rev 1.2, 256MB, Egoman * 0006 - Model B, Rev 1.2, 256MB, Egoman * * 0007 - Model A, Rev 1.2, 256MB, Egoman * 0008 - Model A, Rev 1.2, 256MB, Sony * 0009 - Model A, Rev 1.2, 256MB, Egoman * * 000d - Model B, Rev 1.2, 512MB, Egoman (Red Pi, Blue Pi?) * 000e - Model B, Rev 1.2, 512MB, Sony * 000f - Model B, Rev 1.2, 512MB, Egoman * * 0010 - Model B+, Rev 1.2, 512MB, Sony * 0013 - Model B+ Rev 1.2, 512MB, Embest * 0016 - Model B+ Rev 1.2, 512MB, Sony * 0019 - Model B+ Rev 1.2, 512MB, Egoman * * 0011 - Pi CM, Rev 1.1, 512MB, Sony * 0014 - Pi CM, Rev 1.1, 512MB, Embest * 0017 - Pi CM, Rev 1.1, 512MB, Sony * 001a - Pi CM, Rev 1.1, 512MB, Egoman * * 0012 - Model A+ Rev 1.1, 256MB, Sony * 0015 - Model A+ Rev 1.1, 512MB, Embest * 0018 - Model A+ Rev 1.1, 256MB, Sony * 001b - Model A+ Rev 1.1, 256MB, Egoman * * A small thorn is the olde style overvolting - that will add in * 1000000 * * The Pi compute module has an revision of 0011 or 0014 - since we only * check the last digit, then it's 1, therefore it'll default to not 2 or * 3 for a Rev 1, so will appear as a Rev 2. This is fine for the most part, but * we'll properly detect the Compute Module later and adjust accordingly. * * And then things changed with the introduction of the v2... * * For Pi v2 and subsequent models - e.g. the Zero: * * [USER:8] [NEW:1] [MEMSIZE:3] [MANUFACTURER:4] [PROCESSOR:4] [TYPE:8] [REV:4] * NEW 23: will be 1 for the new scheme, 0 for the old scheme * MEMSIZE 20: 0=256M 1=512M 2=1G * MANUFACTURER 16: 0=SONY 1=EGOMAN 2=EMBEST * PROCESSOR 12: 0=2835 1=2836 * TYPE 04: 0=MODELA 1=MODELB 2=MODELA+ 3=MODELB+ 4=Pi2 MODEL B 5=ALPHA 6=CM * REV 00: 0=REV0 1=REV1 2=REV2 ********************************************************************************* */ void piBoardId (int *model, int *rev, int *mem, int *maker, int *warranty) { FILE *cpuFd ; char line [120] ; char *c ; unsigned int revision ; int bRev, bType, bProc, bMfg, bMem, bWarranty ; // Will deal with the properly later on - for now, lets just get it going... // unsigned int modelNum ; (void)piGpioLayout () ; // Call this first to make sure all's OK. Don't care about the result. if ((cpuFd = fopen ("/proc/cpuinfo", "r")) == NULL) piGpioLayoutOops ("Unable to open /proc/cpuinfo") ; while (fgets (line, 120, cpuFd) != NULL) if (strncmp (line, "Revision", 8) == 0) break ; fclose (cpuFd) ; if (strncmp (line, "Revision", 8) != 0) piGpioLayoutOops ("No \"Revision\" line") ; // Chomp trailing CR/NL for (c = &line [strlen (line) - 1] ; (*c == '\n') || (*c == '\r') ; --c) *c = 0 ; if (wiringPiDebug) printf ("piBoardId: Revision string: %s\n", line) ; // Need to work out if it's using the new or old encoding scheme: // Scan to the first character of the revision number for (c = line ; *c ; ++c) if (*c == ':') break ; if (*c != ':') piGpioLayoutOops ("Bogus \"Revision\" line (no colon)") ; // Chomp spaces ++c ; while (isspace (*c)) ++c ; if (!isxdigit (*c)) piGpioLayoutOops ("Bogus \"Revision\" line (no hex digit at start of revision)") ; revision = (unsigned int)strtol (c, NULL, 16) ; // Hex number with no leading 0x // Check for new way: if ((revision & (1 << 23)) != 0) // New way { if (wiringPiDebug) printf ("piBoardId: New Way: revision is: 0x%08X\n", revision) ; bRev = (revision & (0x0F << 0)) >> 0 ; bType = (revision & (0xFF << 4)) >> 4 ; bProc = (revision & (0x0F << 12)) >> 12 ; // Not used for now. bMfg = (revision & (0x0F << 16)) >> 16 ; bMem = (revision & (0x07 << 20)) >> 20 ; bWarranty = (revision & (0x03 << 24)) != 0 ; *model = bType ; *rev = bRev ; *mem = bMem ; *maker = bMfg ; *warranty = bWarranty ; if (wiringPiDebug) printf ("piBoardId: rev: %d, type: %d, proc: %d, mfg: %d, mem: %d, warranty: %d\n", bRev, bType, bProc, bMfg, bMem, bWarranty) ; } else // Old way { if (wiringPiDebug) printf ("piBoardId: Old Way: revision is: %s\n", c) ; if (!isdigit (*c)) piGpioLayoutOops ("Bogus \"Revision\" line (no digit at start of revision)") ; // Make sure its long enough if (strlen (c) < 4) piGpioLayoutOops ("Bogus \"Revision\" line (not long enough)") ; // If longer than 4, we'll assume it's been overvolted *warranty = strlen (c) > 4 ; // Extract last 4 characters: c = c + strlen (c) - 4 ; // Fill out the replys as appropriate /**/ if (strcmp (c, "0002") == 0) { *model = PI_MODEL_B ; *rev = PI_VERSION_1 ; *mem = 0 ; *maker = PI_MAKER_EGOMAN ; } else if (strcmp (c, "0003") == 0) { *model = PI_MODEL_B ; *rev = PI_VERSION_1_1 ; *mem = 0 ; *maker = PI_MAKER_EGOMAN ; } else if (strcmp (c, "0004") == 0) { *model = PI_MODEL_B ; *rev = PI_VERSION_1_2 ; *mem = 0 ; *maker = PI_MAKER_SONY ; } else if (strcmp (c, "0005") == 0) { *model = PI_MODEL_B ; *rev = PI_VERSION_1_2 ; *mem = 0 ; *maker = PI_MAKER_EGOMAN ; } else if (strcmp (c, "0006") == 0) { *model = PI_MODEL_B ; *rev = PI_VERSION_1_2 ; *mem = 0 ; *maker = PI_MAKER_EGOMAN ; } else if (strcmp (c, "0007") == 0) { *model = PI_MODEL_A ; *rev = PI_VERSION_1_2 ; *mem = 0 ; *maker = PI_MAKER_EGOMAN ; } else if (strcmp (c, "0008") == 0) { *model = PI_MODEL_A ; *rev = PI_VERSION_1_2 ; *mem = 0 ; *maker = PI_MAKER_SONY ; ; } else if (strcmp (c, "0009") == 0) { *model = PI_MODEL_A ; *rev = PI_VERSION_1_2 ; *mem = 0 ; *maker = PI_MAKER_EGOMAN ; } else if (strcmp (c, "000d") == 0) { *model = PI_MODEL_B ; *rev = PI_VERSION_1_2 ; *mem = 1 ; *maker = PI_MAKER_EGOMAN ; } else if (strcmp (c, "000e") == 0) { *model = PI_MODEL_B ; *rev = PI_VERSION_1_2 ; *mem = 1 ; *maker = PI_MAKER_SONY ; } else if (strcmp (c, "000f") == 0) { *model = PI_MODEL_B ; *rev = PI_VERSION_1_2 ; *mem = 1 ; *maker = PI_MAKER_EGOMAN ; } else if (strcmp (c, "0010") == 0) { *model = PI_MODEL_BP ; *rev = PI_VERSION_1_2 ; *mem = 1 ; *maker = PI_MAKER_SONY ; } else if (strcmp (c, "0013") == 0) { *model = PI_MODEL_BP ; *rev = PI_VERSION_1_2 ; *mem = 1 ; *maker = PI_MAKER_EMBEST ; } else if (strcmp (c, "0016") == 0) { *model = PI_MODEL_BP ; *rev = PI_VERSION_1_2 ; *mem = 1 ; *maker = PI_MAKER_SONY ; } else if (strcmp (c, "0019") == 0) { *model = PI_MODEL_BP ; *rev = PI_VERSION_1_2 ; *mem = 1 ; *maker = PI_MAKER_EGOMAN ; } else if (strcmp (c, "0011") == 0) { *model = PI_MODEL_CM ; *rev = PI_VERSION_1_1 ; *mem = 1 ; *maker = PI_MAKER_SONY ; } else if (strcmp (c, "0014") == 0) { *model = PI_MODEL_CM ; *rev = PI_VERSION_1_1 ; *mem = 1 ; *maker = PI_MAKER_EMBEST ; } else if (strcmp (c, "0017") == 0) { *model = PI_MODEL_CM ; *rev = PI_VERSION_1_1 ; *mem = 1 ; *maker = PI_MAKER_SONY ; } else if (strcmp (c, "001a") == 0) { *model = PI_MODEL_CM ; *rev = PI_VERSION_1_1 ; *mem = 1 ; *maker = PI_MAKER_EGOMAN ; } else if (strcmp (c, "0012") == 0) { *model = PI_MODEL_AP ; *rev = PI_VERSION_1_1 ; *mem = 0 ; *maker = PI_MAKER_SONY ; } else if (strcmp (c, "0015") == 0) { *model = PI_MODEL_AP ; *rev = PI_VERSION_1_1 ; *mem = 1 ; *maker = PI_MAKER_EMBEST ; } else if (strcmp (c, "0018") == 0) { *model = PI_MODEL_AP ; *rev = PI_VERSION_1_1 ; *mem = 0 ; *maker = PI_MAKER_SONY ; } else if (strcmp (c, "001b") == 0) { *model = PI_MODEL_AP ; *rev = PI_VERSION_1_1 ; *mem = 0 ; *maker = PI_MAKER_EGOMAN ; } else { *model = 0 ; *rev = 0 ; *mem = 0 ; *maker = 0 ; } } } /* * wpiPinToGpio: * Translate a wiringPi Pin number to native GPIO pin number. * Provided for external support. ********************************************************************************* */ int wpiPinToGpio (int wpiPin) { return pinToGpio [wpiPin & 63] ; } /* * physPinToGpio: * Translate a physical Pin number to native GPIO pin number. * Provided for external support. ********************************************************************************* */ int physPinToGpio (int physPin) { return physToGpio [physPin & 63] ; } /* * setPadDrive: * Set the PAD driver value ********************************************************************************* */ void setPadDrive (int group, int value) { uint32_t wrVal ; if ((wiringPiMode == WPI_MODE_PINS) || (wiringPiMode == WPI_MODE_PHYS) || (wiringPiMode == WPI_MODE_GPIO)) { if ((group < 0) || (group > 2)) return ; wrVal = BCM_PASSWORD | 0x18 | (value & 7) ; *(pads + group + 11) = wrVal ; if (wiringPiDebug) { printf ("setPadDrive: Group: %d, value: %d (%08X)\n", group, value, wrVal) ; printf ("Read : %08X\n", *(pads + group + 11)) ; } } } /* * getAlt: * Returns the ALT bits for a given port. Only really of-use * for the gpio readall command (I think) ********************************************************************************* */ int getAlt (int pin) { int fSel, shift, alt ; pin &= 63 ; /**/ if (wiringPiMode == WPI_MODE_PINS) pin = pinToGpio [pin] ; else if (wiringPiMode == WPI_MODE_PHYS) pin = physToGpio [pin] ; else if (wiringPiMode != WPI_MODE_GPIO) return 0 ; fSel = gpioToGPFSEL [pin] ; shift = gpioToShift [pin] ; alt = (*(gpio + fSel) >> shift) & 7 ; return alt ; } /* * pwmSetMode: * Select the native "balanced" mode, or standard mark:space mode ********************************************************************************* */ void pwmSetMode (int mode) { if ((wiringPiMode == WPI_MODE_PINS) || (wiringPiMode == WPI_MODE_PHYS) || (wiringPiMode == WPI_MODE_GPIO)) { if (mode == PWM_MODE_MS) *(pwm + PWM_CONTROL) = PWM0_ENABLE | PWM1_ENABLE | PWM0_MS_MODE | PWM1_MS_MODE ; else *(pwm + PWM_CONTROL) = PWM0_ENABLE | PWM1_ENABLE ; } } /* * pwmSetRange: * Set the PWM range register. We set both range registers to the same * value. If you want different in your own code, then write your own. ********************************************************************************* */ void pwmSetRange (unsigned int range) { if ((wiringPiMode == WPI_MODE_PINS) || (wiringPiMode == WPI_MODE_PHYS) || (wiringPiMode == WPI_MODE_GPIO)) { *(pwm + PWM0_RANGE) = range ; delayMicroseconds (10) ; *(pwm + PWM1_RANGE) = range ; delayMicroseconds (10) ; } } /* * pwmSetClock: * Set/Change the PWM clock. Originally my code, but changed * (for the better!) by Chris Hall, * after further study of the manual and testing with a 'scope ********************************************************************************* */ void pwmSetClock (int divisor) { uint32_t pwm_control ; divisor &= 4095 ; if ((wiringPiMode == WPI_MODE_PINS) || (wiringPiMode == WPI_MODE_PHYS) || (wiringPiMode == WPI_MODE_GPIO)) { if (wiringPiDebug) printf ("Setting to: %d. Current: 0x%08X\n", divisor, *(clk + PWMCLK_DIV)) ; pwm_control = *(pwm + PWM_CONTROL) ; // preserve PWM_CONTROL // We need to stop PWM prior to stopping PWM clock in MS mode otherwise BUSY // stays high. *(pwm + PWM_CONTROL) = 0 ; // Stop PWM // Stop PWM clock before changing divisor. The delay after this does need to // this big (95uS occasionally fails, 100uS OK), it's almost as though the BUSY // flag is not working properly in balanced mode. Without the delay when DIV is // adjusted the clock sometimes switches to very slow, once slow further DIV // adjustments do nothing and it's difficult to get out of this mode. *(clk + PWMCLK_CNTL) = BCM_PASSWORD | 0x01 ; // Stop PWM Clock delayMicroseconds (110) ; // prevents clock going sloooow while ((*(clk + PWMCLK_CNTL) & 0x80) != 0) // Wait for clock to be !BUSY delayMicroseconds (1) ; *(clk + PWMCLK_DIV) = BCM_PASSWORD | (divisor << 12) ; *(clk + PWMCLK_CNTL) = BCM_PASSWORD | 0x11 ; // Start PWM clock *(pwm + PWM_CONTROL) = pwm_control ; // restore PWM_CONTROL if (wiringPiDebug) printf ("Set to: %d. Now : 0x%08X\n", divisor, *(clk + PWMCLK_DIV)) ; } } /* * gpioClockSet: * Set the freuency on a GPIO clock pin ********************************************************************************* */ void gpioClockSet (int pin, int freq) { int divi, divr, divf ; pin &= 63 ; /**/ if (wiringPiMode == WPI_MODE_PINS) pin = pinToGpio [pin] ; else if (wiringPiMode == WPI_MODE_PHYS) pin = physToGpio [pin] ; else if (wiringPiMode != WPI_MODE_GPIO) return ; divi = 19200000 / freq ; divr = 19200000 % freq ; divf = (int)((double)divr * 4096.0 / 19200000.0) ; if (divi > 4095) divi = 4095 ; *(clk + gpioToClkCon [pin]) = BCM_PASSWORD | GPIO_CLOCK_SOURCE ; // Stop GPIO Clock while ((*(clk + gpioToClkCon [pin]) & 0x80) != 0) // ... and wait ; *(clk + gpioToClkDiv [pin]) = BCM_PASSWORD | (divi << 12) | divf ; // Set dividers *(clk + gpioToClkCon [pin]) = BCM_PASSWORD | 0x10 | GPIO_CLOCK_SOURCE ; // Start Clock } /* * wiringPiFindNode: * Locate our device node ********************************************************************************* */ struct wiringPiNodeStruct *wiringPiFindNode (int pin) { struct wiringPiNodeStruct *node = wiringPiNodes ; while (node != NULL) if ((pin >= node->pinBase) && (pin <= node->pinMax)) return node ; else node = node->next ; return NULL ; } /* * wiringPiNewNode: * Create a new GPIO node into the wiringPi handling system ********************************************************************************* */ static void pinModeDummy (UNU struct wiringPiNodeStruct *node, UNU int pin, UNU int mode) { return ; } static void pullUpDnControlDummy (UNU struct wiringPiNodeStruct *node, UNU int pin, UNU int pud) { return ; } static unsigned int digitalRead8Dummy (UNU struct wiringPiNodeStruct *node, UNU int UNU pin) { return 0 ; } static void digitalWrite8Dummy (UNU struct wiringPiNodeStruct *node, UNU int pin, UNU int value) { return ; } static int digitalReadDummy (UNU struct wiringPiNodeStruct *node, UNU int UNU pin) { return LOW ; } static void digitalWriteDummy (UNU struct wiringPiNodeStruct *node, UNU int pin, UNU int value) { return ; } static void pwmWriteDummy (UNU struct wiringPiNodeStruct *node, UNU int pin, UNU int value) { return ; } static int analogReadDummy (UNU struct wiringPiNodeStruct *node, UNU int pin) { return 0 ; } static void analogWriteDummy (UNU struct wiringPiNodeStruct *node, UNU int pin, UNU int value) { return ; } struct wiringPiNodeStruct *wiringPiNewNode (int pinBase, int numPins) { int pin ; struct wiringPiNodeStruct *node ; // Minimum pin base is 64 if (pinBase < 64) (void)wiringPiFailure (WPI_FATAL, "wiringPiNewNode: pinBase of %d is < 64\n", pinBase) ; // Check all pins in-case there is overlap: for (pin = pinBase ; pin < (pinBase + numPins) ; ++pin) if (wiringPiFindNode (pin) != NULL) (void)wiringPiFailure (WPI_FATAL, "wiringPiNewNode: Pin %d overlaps with existing definition\n", pin) ; node = (struct wiringPiNodeStruct *)calloc (sizeof (struct wiringPiNodeStruct), 1) ; // calloc zeros if (node == NULL) (void)wiringPiFailure (WPI_FATAL, "wiringPiNewNode: Unable to allocate memory: %s\n", strerror (errno)) ; node->pinBase = pinBase ; node->pinMax = pinBase + numPins - 1 ; node->pinMode = pinModeDummy ; node->pullUpDnControl = pullUpDnControlDummy ; node->digitalRead = digitalReadDummy ; //node->digitalRead8 = digitalRead8Dummy ; node->digitalWrite = digitalWriteDummy ; //node->digitalWrite8 = digitalWrite8Dummy ; node->pwmWrite = pwmWriteDummy ; node->analogRead = analogReadDummy ; node->analogWrite = analogWriteDummy ; node->next = wiringPiNodes ; wiringPiNodes = node ; return node ; } #ifdef notYetReady /* * pinED01: * pinED10: * Enables edge-detect mode on a pin - from a 0 to a 1 or 1 to 0 * Pin must already be in input mode with appropriate pull up/downs set. ********************************************************************************* */ void pinEnableED01Pi (int pin) { pin = pinToGpio [pin & 63] ; } #endif /* ********************************************************************************* * Core Functions ********************************************************************************* */ /* * pinModeAlt: * This is an un-documented special to let you set any pin to any mode ********************************************************************************* */ void pinModeAlt (int pin, int mode) { int fSel, shift ; if ((pin & PI_GPIO_MASK) == 0) // On-board pin { /**/ if (wiringPiMode == WPI_MODE_PINS) pin = pinToGpio [pin] ; else if (wiringPiMode == WPI_MODE_PHYS) pin = physToGpio [pin] ; else if (wiringPiMode != WPI_MODE_GPIO) return ; fSel = gpioToGPFSEL [pin] ; shift = gpioToShift [pin] ; *(gpio + fSel) = (*(gpio + fSel) & ~(7 << shift)) | ((mode & 0x7) << shift) ; } } /* * pinMode: * Sets the mode of a pin to be input, output or PWM output ********************************************************************************* */ void pinMode (int pin, int mode) { int fSel, shift, alt ; struct wiringPiNodeStruct *node = wiringPiNodes ; int origPin = pin ; if ((pin & PI_GPIO_MASK) == 0) // On-board pin { /**/ if (wiringPiMode == WPI_MODE_PINS) pin = pinToGpio [pin] ; else if (wiringPiMode == WPI_MODE_PHYS) pin = physToGpio [pin] ; else if (wiringPiMode != WPI_MODE_GPIO) return ; softPwmStop (origPin) ; softToneStop (origPin) ; fSel = gpioToGPFSEL [pin] ; shift = gpioToShift [pin] ; /**/ if (mode == INPUT) *(gpio + fSel) = (*(gpio + fSel) & ~(7 << shift)) ; // Sets bits to zero = input else if (mode == OUTPUT) *(gpio + fSel) = (*(gpio + fSel) & ~(7 << shift)) | (1 << shift) ; else if (mode == SOFT_PWM_OUTPUT) softPwmCreate (origPin, 0, 100) ; else if (mode == SOFT_TONE_OUTPUT) softToneCreate (origPin) ; else if (mode == PWM_TONE_OUTPUT) { pinMode (origPin, PWM_OUTPUT) ; // Call myself to enable PWM mode pwmSetMode (PWM_MODE_MS) ; } else if (mode == PWM_OUTPUT) { if ((alt = gpioToPwmALT [pin]) == 0) // Not a hardware capable PWM pin return ; // Set pin to PWM mode *(gpio + fSel) = (*(gpio + fSel) & ~(7 << shift)) | (alt << shift) ; delayMicroseconds (110) ; // See comments in pwmSetClockWPi pwmSetMode (PWM_MODE_BAL) ; // Pi default mode pwmSetRange (1024) ; // Default range of 1024 pwmSetClock (32) ; // 19.2 / 32 = 600KHz - Also starts the PWM } else if (mode == GPIO_CLOCK) { if ((alt = gpioToGpClkALT0 [pin]) == 0) // Not a GPIO_CLOCK pin return ; // Set pin to GPIO_CLOCK mode and set the clock frequency to 100KHz *(gpio + fSel) = (*(gpio + fSel) & ~(7 << shift)) | (alt << shift) ; delayMicroseconds (110) ; gpioClockSet (pin, 100000) ; } } else { if ((node = wiringPiFindNode (pin)) != NULL) node->pinMode (node, pin, mode) ; return ; } } /* * pullUpDownCtrl: * Control the internal pull-up/down resistors on a GPIO pin * The Arduino only has pull-ups and these are enabled by writing 1 * to a port when in input mode - this paradigm doesn't quite apply * here though. ********************************************************************************* */ void pullUpDnControl (int pin, int pud) { struct wiringPiNodeStruct *node = wiringPiNodes ; if ((pin & PI_GPIO_MASK) == 0) // On-Board Pin { /**/ if (wiringPiMode == WPI_MODE_PINS) pin = pinToGpio [pin] ; else if (wiringPiMode == WPI_MODE_PHYS) pin = physToGpio [pin] ; else if (wiringPiMode != WPI_MODE_GPIO) return ; *(gpio + GPPUD) = pud & 3 ; delayMicroseconds (5) ; *(gpio + gpioToPUDCLK [pin]) = 1 << (pin & 31) ; delayMicroseconds (5) ; *(gpio + GPPUD) = 0 ; delayMicroseconds (5) ; *(gpio + gpioToPUDCLK [pin]) = 0 ; delayMicroseconds (5) ; } else // Extension module { if ((node = wiringPiFindNode (pin)) != NULL) node->pullUpDnControl (node, pin, pud) ; return ; } } /* * digitalRead: * Read the value of a given Pin, returning HIGH or LOW ********************************************************************************* */ int digitalRead (int pin) { char c ; struct wiringPiNodeStruct *node = wiringPiNodes ; if ((pin & PI_GPIO_MASK) == 0) // On-Board Pin { /**/ if (wiringPiMode == WPI_MODE_GPIO_SYS) // Sys mode { if (sysFds [pin] == -1) return LOW ; lseek (sysFds [pin], 0L, SEEK_SET) ; read (sysFds [pin], &c, 1) ; return (c == '0') ? LOW : HIGH ; } else if (wiringPiMode == WPI_MODE_PINS) pin = pinToGpio [pin] ; else if (wiringPiMode == WPI_MODE_PHYS) pin = physToGpio [pin] ; else if (wiringPiMode != WPI_MODE_GPIO) return LOW ; if ((*(gpio + gpioToGPLEV [pin]) & (1 << (pin & 31))) != 0) return HIGH ; else return LOW ; } else { if ((node = wiringPiFindNode (pin)) == NULL) return LOW ; return node->digitalRead (node, pin) ; } } /* * digitalRead8: * Read 8-bits (a byte) from given start pin. ********************************************************************************* unsigned int digitalRead8 (int pin) { struct wiringPiNodeStruct *node = wiringPiNodes ; if ((pin & PI_GPIO_MASK) == 0) // On-Board Pin return 0 ; else { if ((node = wiringPiFindNode (pin)) == NULL) return LOW ; return node->digitalRead8 (node, pin) ; } } */ /* * digitalWrite: * Set an output bit ********************************************************************************* */ void digitalWrite (int pin, int value) { struct wiringPiNodeStruct *node = wiringPiNodes ; if ((pin & PI_GPIO_MASK) == 0) // On-Board Pin { /**/ if (wiringPiMode == WPI_MODE_GPIO_SYS) // Sys mode { if (sysFds [pin] != -1) { if (value == LOW) write (sysFds [pin], "0\n", 2) ; else write (sysFds [pin], "1\n", 2) ; } return ; } else if (wiringPiMode == WPI_MODE_PINS) pin = pinToGpio [pin] ; else if (wiringPiMode == WPI_MODE_PHYS) pin = physToGpio [pin] ; else if (wiringPiMode != WPI_MODE_GPIO) return ; if (value == LOW) *(gpio + gpioToGPCLR [pin]) = 1 << (pin & 31) ; else *(gpio + gpioToGPSET [pin]) = 1 << (pin & 31) ; } else { if ((node = wiringPiFindNode (pin)) != NULL) node->digitalWrite (node, pin, value) ; } } /* * digitalWrite8: * Set an output 8-bit byte on the device from the given pin number ********************************************************************************* void digitalWrite8 (int pin, int value) { struct wiringPiNodeStruct *node = wiringPiNodes ; if ((pin & PI_GPIO_MASK) == 0) // On-Board Pin return ; else { if ((node = wiringPiFindNode (pin)) != NULL) node->digitalWrite8 (node, pin, value) ; } } */ /* * pwmWrite: * Set an output PWM value ********************************************************************************* */ void pwmWrite (int pin, int value) { struct wiringPiNodeStruct *node = wiringPiNodes ; if ((pin & PI_GPIO_MASK) == 0) // On-Board Pin { /**/ if (wiringPiMode == WPI_MODE_PINS) pin = pinToGpio [pin] ; else if (wiringPiMode == WPI_MODE_PHYS) pin = physToGpio [pin] ; else if (wiringPiMode != WPI_MODE_GPIO) return ; *(pwm + gpioToPwmPort [pin]) = value ; } else { if ((node = wiringPiFindNode (pin)) != NULL) node->pwmWrite (node, pin, value) ; } } /* * analogRead: * Read the analog value of a given Pin. * There is no on-board Pi analog hardware, * so this needs to go to a new node. ********************************************************************************* */ int analogRead (int pin) { struct wiringPiNodeStruct *node = wiringPiNodes ; if ((node = wiringPiFindNode (pin)) == NULL) return 0 ; else return node->analogRead (node, pin) ; } /* * analogWrite: * Write the analog value to the given Pin. * There is no on-board Pi analog hardware, * so this needs to go to a new node. ********************************************************************************* */ void analogWrite (int pin, int value) { struct wiringPiNodeStruct *node = wiringPiNodes ; if ((node = wiringPiFindNode (pin)) == NULL) return ; node->analogWrite (node, pin, value) ; } /* * pwmToneWrite: * Pi Specific. * Output the given frequency on the Pi's PWM pin ********************************************************************************* */ void pwmToneWrite (int pin, int freq) { int range ; if (freq == 0) pwmWrite (pin, 0) ; // Off else { range = 600000 / freq ; pwmSetRange (range) ; pwmWrite (pin, freq / 2) ; } } /* * digitalWriteByte: * digitalReadByte: * Pi Specific * Write an 8-bit byte to the first 8 GPIO pins - try to do it as * fast as possible. * However it still needs 2 operations to set the bits, so any external * hardware must not rely on seeing a change as there will be a change * to set the outputs bits to zero, then another change to set the 1's * Reading is just bit fiddling. * These are wiringPi pin numbers 0..7, or BCM_GPIO pin numbers * 17, 18, 22, 23, 24, 24, 4 on a Pi v1 rev 0-3 * 17, 18, 27, 23, 24, 24, 4 on a Pi v1 rev 3 onwards or B+, 2, 3, zero ********************************************************************************* */ void digitalWriteByte (const int value) { uint32_t pinSet = 0 ; uint32_t pinClr = 0 ; int mask = 1 ; int pin ; /**/ if (wiringPiMode == WPI_MODE_GPIO_SYS) { for (pin = 0 ; pin < 8 ; ++pin) { digitalWrite (pinToGpio [pin], value & mask) ; mask <<= 1 ; } return ; } else { for (pin = 0 ; pin < 8 ; ++pin) { if ((value & mask) == 0) pinClr |= (1 << pinToGpio [pin]) ; else pinSet |= (1 << pinToGpio [pin]) ; mask <<= 1 ; } *(gpio + gpioToGPCLR [0]) = pinClr ; *(gpio + gpioToGPSET [0]) = pinSet ; } } unsigned int digitalReadByte (void) { int pin, x ; uint32_t raw ; uint32_t data = 0 ; /**/ if (wiringPiMode == WPI_MODE_GPIO_SYS) { for (pin = 0 ; pin < 8 ; ++pin) { x = digitalRead (pinToGpio [pin]) ; data = (data << 1) | x ; } } else { raw = *(gpio + gpioToGPLEV [0]) ; // First bank for these pins for (pin = 0 ; pin < 8 ; ++pin) { x = pinToGpio [pin] ; data = (data << 1) | (((raw & (1 << x)) == 0) ? 0 : 1) ; } } return data ; } /* * digitalWriteByte2: * digitalReadByte2: * Pi Specific * Write an 8-bit byte to the second set of 8 GPIO pins. This is marginally * faster than the first lot as these are consecutive BCM_GPIO pin numbers. * However they overlap with the original read/write bytes. ********************************************************************************* */ void digitalWriteByte2 (const int value) { register int mask = 1 ; register int pin ; /**/ if (wiringPiMode == WPI_MODE_GPIO_SYS) { for (pin = 20 ; pin < 28 ; ++pin) { digitalWrite (pin, value & mask) ; mask <<= 1 ; } return ; } else { *(gpio + gpioToGPCLR [0]) = (~value & 0xFF) << 20 ; // 0x0FF00000; ILJ > CHANGE: Old causes glitch *(gpio + gpioToGPSET [0]) = ( value & 0xFF) << 20 ; } } unsigned int digitalReadByte2 (void) { int pin, x ; uint32_t data = 0 ; /**/ if (wiringPiMode == WPI_MODE_GPIO_SYS) { for (pin = 20 ; pin < 28 ; ++pin) { x = digitalRead (pin) ; data = (data << 1) | x ; } } else data = ((*(gpio + gpioToGPLEV [0])) >> 20) & 0xFF ; // First bank for these pins return data ; } /* * waitForInterrupt: * Pi Specific. * Wait for Interrupt on a GPIO pin. * This is actually done via the /sys/class/gpio interface regardless of * the wiringPi access mode in-use. Maybe sometime it might get a better * way for a bit more efficiency. ********************************************************************************* */ int waitForInterrupt (int pin, int mS) { int fd, x ; uint8_t c ; struct pollfd polls ; /**/ if (wiringPiMode == WPI_MODE_PINS) pin = pinToGpio [pin] ; else if (wiringPiMode == WPI_MODE_PHYS) pin = physToGpio [pin] ; if ((fd = sysFds [pin]) == -1) return -2 ; // Setup poll structure polls.fd = fd ; polls.events = POLLPRI | POLLERR ; // Wait for it ... x = poll (&polls, 1, mS) ; // If no error, do a dummy read to clear the interrupt // A one character read appars to be enough. if (x > 0) { lseek (fd, 0, SEEK_SET) ; // Rewind (void)read (fd, &c, 1) ; // Read & clear } return x ; } /* * interruptHandler: * This is a thread and gets started to wait for the interrupt we're * hoping to catch. It will call the user-function when the interrupt * fires. ********************************************************************************* */ static void *interruptHandler (UNU void *arg) { int myPin ; (void)piHiPri (55) ; // Only effective if we run as root myPin = pinPass ; pinPass = -1 ; for (;;) if (waitForInterrupt (myPin, -1) > 0) isrFunctions [myPin] () ; return NULL ; } /* * wiringPiISR: * Pi Specific. * Take the details and create an interrupt handler that will do a call- * back to the user supplied function. ********************************************************************************* */ pthread_t threadIds [64]; int wiringPiISR (int pin, int mode, void (*function)(void)) { //pthread_t threadId ; const char *modeS ; char fName [64] ; char pinS [8] ; pid_t pid ; int count, i ; char c ; int bcmGpioPin ; if ((pin < 0) || (pin > 63)) return wiringPiFailure (WPI_FATAL, "wiringPiISR: pin must be 0-63 (%d)\n", pin) ; /**/ if (wiringPiMode == WPI_MODE_UNINITIALISED) return wiringPiFailure (WPI_FATAL, "wiringPiISR: wiringPi has not been initialised. Unable to continue.\n") ; else if (wiringPiMode == WPI_MODE_PINS) bcmGpioPin = pinToGpio [pin] ; else if (wiringPiMode == WPI_MODE_PHYS) bcmGpioPin = physToGpio [pin] ; else bcmGpioPin = pin ; // Now export the pin and set the right edge // We're going to use the gpio program to do this, so it assumes // a full installation of wiringPi. It's a bit 'clunky', but it // is a way that will work when we're running in "Sys" mode, as // a non-root user. (without sudo) if (mode != INT_EDGE_SETUP) { /**/ if (mode == INT_EDGE_FALLING) modeS = "falling" ; else if (mode == INT_EDGE_RISING) modeS = "rising" ; else modeS = "both" ; sprintf (pinS, "%d", bcmGpioPin) ; if ((pid = fork ()) < 0) // Fail return wiringPiFailure (WPI_FATAL, "wiringPiISR: fork failed: %s\n", strerror (errno)) ; if (pid == 0) // Child, exec { /**/ if (access ("/usr/local/bin/gpio", X_OK) == 0) { execl ("/usr/local/bin/gpio", "gpio", "edge", pinS, modeS, (char *)NULL) ; return wiringPiFailure (WPI_FATAL, "wiringPiISR: execl failed: %s\n", strerror (errno)) ; } else if (access ("/usr/bin/gpio", X_OK) == 0) { execl ("/usr/bin/gpio", "gpio", "edge", pinS, modeS, (char *)NULL) ; return wiringPiFailure (WPI_FATAL, "wiringPiISR: execl failed: %s\n", strerror (errno)) ; } else return wiringPiFailure (WPI_FATAL, "wiringPiISR: Can't find gpio program\n") ; } else // Parent, wait wait (NULL) ; } // Now pre-open the /sys/class node - but it may already be open if // we are in Sys mode... if (sysFds [bcmGpioPin] == -1) { sprintf (fName, "/sys/class/gpio/gpio%d/value", bcmGpioPin) ; if ((sysFds [bcmGpioPin] = open (fName, O_RDWR)) < 0) return wiringPiFailure (WPI_FATAL, "wiringPiISR: unable to open %s: %s\n", fName, strerror (errno)) ; } // Clear any initial pending interrupt ioctl (sysFds [bcmGpioPin], FIONREAD, &count) ; for (i = 0 ; i < count ; ++i) read (sysFds [bcmGpioPin], &c, 1) ; isrFunctions [pin] = function ; pthread_mutex_lock (&pinMutex) ; pinPass = pin ; pthread_create (&threadIds[pin], NULL, interruptHandler, NULL) ; while (pinPass != -1) delay (1) ; pthread_mutex_unlock (&pinMutex) ; return 0 ; } int wiringPiISRCancel(int pin) { return pthread_cancel(threadIds[pin]); } /* * initialiseEpoch: * Initialise our start-of-time variable to be the current unix * time in milliseconds and microseconds. ********************************************************************************* */ static void initialiseEpoch (void) { #ifdef OLD_WAY struct timeval tv ; gettimeofday (&tv, NULL) ; epochMilli = (uint64_t)tv.tv_sec * (uint64_t)1000 + (uint64_t)(tv.tv_usec / 1000) ; epochMicro = (uint64_t)tv.tv_sec * (uint64_t)1000000 + (uint64_t)(tv.tv_usec) ; #else struct timespec ts ; clock_gettime (CLOCK_MONOTONIC_RAW, &ts) ; epochMilli = (uint64_t)ts.tv_sec * (uint64_t)1000 + (uint64_t)(ts.tv_nsec / 1000000L) ; epochMicro = (uint64_t)ts.tv_sec * (uint64_t)1000000 + (uint64_t)(ts.tv_nsec / 1000L) ; #endif } /* * delay: * Wait for some number of milliseconds ********************************************************************************* */ void delay (unsigned int howLong) { struct timespec sleeper, dummy ; sleeper.tv_sec = (time_t)(howLong / 1000) ; sleeper.tv_nsec = (long)(howLong % 1000) * 1000000 ; nanosleep (&sleeper, &dummy) ; } /* * delayMicroseconds: * This is somewhat intersting. It seems that on the Pi, a single call * to nanosleep takes some 80 to 130 microseconds anyway, so while * obeying the standards (may take longer), it's not always what we * want! * * So what I'll do now is if the delay is less than 100uS we'll do it * in a hard loop, watching a built-in counter on the ARM chip. This is * somewhat sub-optimal in that it uses 100% CPU, something not an issue * in a microcontroller, but under a multi-tasking, multi-user OS, it's * wastefull, however we've no real choice )-: * * Plan B: It seems all might not be well with that plan, so changing it * to use gettimeofday () and poll on that instead... ********************************************************************************* */ void delayMicrosecondsHard (unsigned int howLong) { struct timeval tNow, tLong, tEnd ; gettimeofday (&tNow, NULL) ; tLong.tv_sec = howLong / 1000000 ; tLong.tv_usec = howLong % 1000000 ; timeradd (&tNow, &tLong, &tEnd) ; while (timercmp (&tNow, &tEnd, <)) gettimeofday (&tNow, NULL) ; } void delayMicroseconds (unsigned int howLong) { struct timespec sleeper ; unsigned int uSecs = howLong % 1000000 ; unsigned int wSecs = howLong / 1000000 ; /**/ if (howLong == 0) return ; else if (howLong < 100) delayMicrosecondsHard (howLong) ; else { sleeper.tv_sec = wSecs ; sleeper.tv_nsec = (long)(uSecs * 1000L) ; nanosleep (&sleeper, NULL) ; } } /* * millis: * Return a number of milliseconds as an unsigned int. * Wraps at 49 days. ********************************************************************************* */ unsigned int millis (void) { uint64_t now ; #ifdef OLD_WAY struct timeval tv ; gettimeofday (&tv, NULL) ; now = (uint64_t)tv.tv_sec * (uint64_t)1000 + (uint64_t)(tv.tv_usec / 1000) ; #else struct timespec ts ; clock_gettime (CLOCK_MONOTONIC_RAW, &ts) ; now = (uint64_t)ts.tv_sec * (uint64_t)1000 + (uint64_t)(ts.tv_nsec / 1000000L) ; #endif return (uint32_t)(now - epochMilli) ; } /* * micros: * Return a number of microseconds as an unsigned int. * Wraps after 71 minutes. ********************************************************************************* */ unsigned int micros (void) { uint64_t now ; #ifdef OLD_WAY struct timeval tv ; gettimeofday (&tv, NULL) ; now = (uint64_t)tv.tv_sec * (uint64_t)1000000 + (uint64_t)tv.tv_usec ; #else struct timespec ts ; clock_gettime (CLOCK_MONOTONIC_RAW, &ts) ; now = (uint64_t)ts.tv_sec * (uint64_t)1000000 + (uint64_t)(ts.tv_nsec / 1000) ; #endif return (uint32_t)(now - epochMicro) ; } /* * wiringPiVersion: * Return our current version number ********************************************************************************* */ void wiringPiVersion (int *major, int *minor) { *major = VERSION_MAJOR ; *minor = VERSION_MINOR ; } /* * wiringPiSetup: * Must be called once at the start of your program execution. * * Default setup: Initialises the system into wiringPi Pin mode and uses the * memory mapped hardware directly. * * Changed now to revert to "gpio" mode if we're running on a Compute Module. ********************************************************************************* */ int wiringPiSetup (void) { int fd ; int model, rev, mem, maker, overVolted ; static int alreadyDoneThis = FALSE ; // It's actually a fatal error to call any of the wiringPiSetup routines more than once, // (you run out of file handles!) but I'm fed-up with the useless twats who email // me bleating that there is a bug in my code, so screw-em. if (alreadyDoneThis) return 0 ; alreadyDoneThis = TRUE ; if (getenv (ENV_DEBUG) != NULL) wiringPiDebug = TRUE ; if (getenv (ENV_CODES) != NULL) wiringPiReturnCodes = TRUE ; if (wiringPiDebug) printf ("wiringPi: wiringPiSetup called\n") ; // Get the board ID information. We're not really using the information here, // but it will give us information like the GPIO layout scheme (2 variants // on the older 26-pin Pi's) and the GPIO peripheral base address. // and if we're running on a compute module, then wiringPi pin numbers // don't really many anything, so force native BCM mode anyway. piBoardId (&model, &rev, &mem, &maker, &overVolted) ; if ((model == PI_MODEL_CM) || (model == PI_MODEL_CM3)) wiringPiMode = WPI_MODE_GPIO ; else wiringPiMode = WPI_MODE_PINS ; /**/ if (piGpioLayout () == 1) // A, B, Rev 1, 1.1 { pinToGpio = pinToGpioR1 ; physToGpio = physToGpioR1 ; } else // A2, B2, A+, B+, CM, Pi2, Pi3, Zero { pinToGpio = pinToGpioR2 ; physToGpio = physToGpioR2 ; } // ... switch (model) { case PI_MODEL_A: case PI_MODEL_B: case PI_MODEL_AP: case PI_MODEL_BP: case PI_ALPHA: case PI_MODEL_CM: case PI_MODEL_ZERO: case PI_MODEL_ZERO_W: piGpioBase = GPIO_PERI_BASE_OLD ; break ; default: piGpioBase = GPIO_PERI_BASE_NEW ; break ; } // Open the master /dev/ memory control device // Device strategy: December 2016: // Try /dev/mem. If that fails, then // try /dev/gpiomem. If that fails then game over. if ((fd = open ("/dev/mem", O_RDWR | O_SYNC | O_CLOEXEC) ) < 0) { if ((fd = open ("/dev/gpiomem", O_RDWR | O_SYNC | O_CLOEXEC) ) < 0) return wiringPiFailure (WPI_ALMOST, "wiringPiSetup: Unable to open /dev/mem or /dev/gpiomem: %s.\n Try running with sudo?\n", strerror (errno)) ; piGpioBase = 0 ; } // Set the offsets into the memory interface. GPIO_PADS = piGpioBase + 0x00100000 ; GPIO_CLOCK_BASE = piGpioBase + 0x00101000 ; GPIO_BASE = piGpioBase + 0x00200000 ; GPIO_TIMER = piGpioBase + 0x0000B000 ; GPIO_PWM = piGpioBase + 0x0020C000 ; // Map the individual hardware components // GPIO: gpio = (uint32_t *)mmap(0, BLOCK_SIZE, PROT_READ|PROT_WRITE, MAP_SHARED, fd, GPIO_BASE) ; if (gpio == MAP_FAILED) return wiringPiFailure (WPI_ALMOST, "wiringPiSetup: mmap (GPIO) failed: %s\n", strerror (errno)) ; // PWM pwm = (uint32_t *)mmap(0, BLOCK_SIZE, PROT_READ|PROT_WRITE, MAP_SHARED, fd, GPIO_PWM) ; if (pwm == MAP_FAILED) return wiringPiFailure (WPI_ALMOST, "wiringPiSetup: mmap (PWM) failed: %s\n", strerror (errno)) ; // Clock control (needed for PWM) clk = (uint32_t *)mmap(0, BLOCK_SIZE, PROT_READ|PROT_WRITE, MAP_SHARED, fd, GPIO_CLOCK_BASE) ; if (clk == MAP_FAILED) return wiringPiFailure (WPI_ALMOST, "wiringPiSetup: mmap (CLOCK) failed: %s\n", strerror (errno)) ; // The drive pads pads = (uint32_t *)mmap(0, BLOCK_SIZE, PROT_READ|PROT_WRITE, MAP_SHARED, fd, GPIO_PADS) ; if (pads == MAP_FAILED) return wiringPiFailure (WPI_ALMOST, "wiringPiSetup: mmap (PADS) failed: %s\n", strerror (errno)) ; #ifdef USE_TIMER // The system timer timer = (uint32_t *)mmap(0, BLOCK_SIZE, PROT_READ|PROT_WRITE, MAP_SHARED, fd, GPIO_TIMER) ; if (timer == MAP_FAILED) return wiringPiFailure (WPI_ALMOST, "wiringPiSetup: mmap (TIMER) failed: %s\n", strerror (errno)) ; // Set the timer to free-running, 1MHz. // 0xF9 is 249, the timer divide is base clock / (divide+1) // so base clock is 250MHz / 250 = 1MHz. *(timer + TIMER_CONTROL) = 0x0000280 ; *(timer + TIMER_PRE_DIV) = 0x00000F9 ; timerIrqRaw = timer + TIMER_IRQ_RAW ; #endif initialiseEpoch () ; return 0 ; } /* * wiringPiSetupGpio: * Must be called once at the start of your program execution. * * GPIO setup: Initialises the system into GPIO Pin mode and uses the * memory mapped hardware directly. ********************************************************************************* */ int wiringPiSetupGpio (void) { (void)wiringPiSetup () ; if (wiringPiDebug) printf ("wiringPi: wiringPiSetupGpio called\n") ; wiringPiMode = WPI_MODE_GPIO ; return 0 ; } /* * wiringPiSetupPhys: * Must be called once at the start of your program execution. * * Phys setup: Initialises the system into Physical Pin mode and uses the * memory mapped hardware directly. ********************************************************************************* */ int wiringPiSetupPhys (void) { (void)wiringPiSetup () ; if (wiringPiDebug) printf ("wiringPi: wiringPiSetupPhys called\n") ; wiringPiMode = WPI_MODE_PHYS ; return 0 ; } /* * wiringPiSetupSys: * Must be called once at the start of your program execution. * * Initialisation (again), however this time we are using the /sys/class/gpio * interface to the GPIO systems - slightly slower, but always usable as * a non-root user, assuming the devices are already exported and setup correctly. */ int wiringPiSetupSys (void) { int pin ; char fName [128] ; static int alreadyDoneThis = FALSE ; // It's actually a fatal error to call any of the wiringPiSetup routines more than once, // (you run out of file handles!) but I'm fed-up with the useless twats who email // me bleating that there is a bug in my code, so screw-em. if (alreadyDoneThis) return 0 ; alreadyDoneThis = TRUE ; if (getenv (ENV_DEBUG) != NULL) wiringPiDebug = TRUE ; if (getenv (ENV_CODES) != NULL) wiringPiReturnCodes = TRUE ; if (wiringPiDebug) printf ("wiringPi: wiringPiSetupSys called\n") ; if (piGpioLayout () == 1) { pinToGpio = pinToGpioR1 ; physToGpio = physToGpioR1 ; } else { pinToGpio = pinToGpioR2 ; physToGpio = physToGpioR2 ; } // Open and scan the directory, looking for exported GPIOs, and pre-open // the 'value' interface to speed things up for later for (pin = 0 ; pin < 64 ; ++pin) { sprintf (fName, "/sys/class/gpio/gpio%d/value", pin) ; sysFds [pin] = open (fName, O_RDWR) ; } initialiseEpoch () ; wiringPiMode = WPI_MODE_GPIO_SYS ; return 0 ; }