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examples/blink12drcs.c

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+/*
+ * blink12drcs.c:
+ *	Simple sequence over the first 12 GPIO pins - LEDs
+ *	Aimed at the Gertboard, but it's fairly generic.
+ *	This version uses DRC totalk to the ATmega on the Gertboard
+ *
+ * Copyright (c) 2012-2013 Gordon Henderson. <projects@drogon.net>
+ ***********************************************************************
+ * 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 <http://www.gnu.org/licenses/>.
+ ***********************************************************************
+ */
+
+#include <stdio.h>
+#include <wiringPi.h>
+#include <drcSerial.h>
+
+#define	GERT_BASE	100
+
+static int pinMap [] =
+{
+  0, 1, 2, 3,		// Pi Native
+  GERT_BASE + 2, GERT_BASE + 3, GERT_BASE + 4, GERT_BASE + 5,
+  GERT_BASE + 6, GERT_BASE + 7, GERT_BASE + 8, GERT_BASE + 9,
+} ;
+
+// Simple sequencer data
+//	Triplets of LED, On/Off and delay
+
+
+int data [] =
+{
+               0, 1, 1,
+               1, 1, 1,
+   0, 0, 0,    2, 1, 1,
+   1, 0, 0,    3, 1, 1,
+   2, 0, 0,    4, 1, 1,
+   3, 0, 0,    5, 1, 1,
+   4, 0, 0,    6, 1, 1,
+   5, 0, 0,    7, 1, 1,
+   6, 0, 0,    8, 1, 1,
+   7, 0, 0,    9, 1, 1,
+   8, 0, 0,   10, 1, 1,
+   9, 0, 0,   11, 1, 1,
+  10, 0, 1,
+  11, 0, 1,
+
+  0, 0, 1,	// Extra delay
+
+// Back again
+
+              11, 1, 1,
+              10, 1, 1,
+  11, 0, 0,    9, 1, 1,
+  10, 0, 0,    8, 1, 1,
+   9, 0, 0,    7, 1, 1,
+   8, 0, 0,    6, 1, 1,
+   7, 0, 0,    5, 1, 1,
+   6, 0, 0,    4, 1, 1,
+   5, 0, 0,    3, 1, 1,
+   4, 0, 0,    2, 1, 1,
+   3, 0, 0,    1, 1, 1,
+   2, 0, 0,    0, 1, 1,
+   1, 0, 1,
+   0, 0, 1,
+
+   0, 0, 1,	// Extra delay
+
+   0, 9, 0,	// End marker
+
+} ;
+
+
+int main (void)
+{
+  int pin ;
+  int dataPtr ;
+  int l, s, d ;
+
+  printf ("Raspberry Pi - 12-LED Sequence\n") ;
+  printf ("==============================\n") ;
+  printf ("\n") ;
+  printf ("Connect LEDs up to the first 4 Pi pins and 8 pins on the ATmega\n") ;
+  printf ("    from PD2 through PB1 in that order,\n") ;
+  printf ("  then sit back and watch the show!\n") ;
+
+  wiringPiSetup  () ;
+  drcSetupSerial (GERT_BASE, 20, "/dev/ttyAMA0", 115200) ;
+
+  for (pin = 0 ; pin < 12 ; ++pin)
+    pinMode (pinMap [pin], OUTPUT) ;
+
+  dataPtr = 0 ;
+
+  for (;;)
+  {
+    l = data [dataPtr++] ;	// LED
+    s = data [dataPtr++] ;	// State
+    d = data [dataPtr++] ;	// Duration (10ths)
+
+    if (s == 9)			// 9 -> End Marker
+    {
+      dataPtr = 0 ;
+      continue ;
+    }
+
+    digitalWrite (pinMap [l], s) ;
+    delay        (d * analogRead (GERT_BASE) / 4) ;
+  }
+
+  return 0 ;
+}

wiringPi/drcSerial.c

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+/*
+ * drcSerial.c:
+ *	Extend wiringPi with the DRC Serial protocol (e.g. to Arduino)
+ *	Copyright (c) 2013 Gordon Henderson
+ ***********************************************************************
+ * 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 <http://www.gnu.org/licenses/>.
+ ***********************************************************************
+ */
+
+#include <stdio.h>
+#include <time.h>
+#include <string.h>
+#include <errno.h>
+
+#include "wiringPi.h"
+#include "wiringSerial.h"
+
+#include "drcSerial.h"
+
+#ifndef	TRUE
+#  define	TRUE	(1==1)
+#  define	FALSE	(1==2)
+#endif
+
+
+/*
+ * myPinMode:
+ *	Change the pin mode on the remote DRC device
+ *********************************************************************************
+ */
+
+static void myPinMode (struct wiringPiNodeStruct *node, int pin, int mode)
+{
+  /**/ if (mode == OUTPUT)
+    serialPutchar (node->fd, 'o') ;       // Input
+  else if (mode == PWM_OUTPUT)
+    serialPutchar (node->fd, 'p') ;       // PWM
+  else
+    serialPutchar (node->fd, 'i') ;       // Default to input
+
+  serialPutchar (node->fd, pin - node->pinBase) ;
+}
+
+
+/*
+ * myPullUpDnControl:
+ *	ATmegas only have pull-up's on of off. No pull-downs.
+ *********************************************************************************
+ */
+
+static void myPullUpDnControl (struct wiringPiNodeStruct *node, int pin, int mode)
+{
+
+// Force pin into input mode
+
+  serialPutchar (node->fd, 'i' ) ;
+  serialPutchar (node->fd, pin - node->pinBase) ;
+
+  /**/ if (mode == PUD_UP)
+  {
+    serialPutchar (node->fd, '1') ;
+    serialPutchar (node->fd, pin - node->pinBase) ;
+  }
+  else if (mode == PUD_OFF)
+  {
+    serialPutchar (node->fd, '0') ;
+    serialPutchar (node->fd, pin - node->pinBase) ;
+  }
+}
+
+
+/*
+ * myDigitalWrite:
+ *********************************************************************************
+ */
+
+static void myDigitalWrite (struct wiringPiNodeStruct *node, int pin, int value)
+{
+  serialPutchar (node->fd, value == 0 ? '0' : '1') ;
+  serialPutchar (node->fd, pin - node->pinBase) ;
+}
+
+
+/*
+ * myPwmWrite:
+ *********************************************************************************
+ */
+
+static void myPwmWrite (struct wiringPiNodeStruct *node, int pin, int value)
+{
+  serialPutchar (node->fd, 'v') ;
+  serialPutchar (node->fd, pin - node->pinBase) ;
+  serialPutchar (node->fd, value & 0xFF) ;
+}
+
+
+/*
+ * myAnalogRead:
+ *********************************************************************************
+ */
+
+static int myAnalogRead (struct wiringPiNodeStruct *node, int pin)
+{
+  int vHi, vLo ;
+
+  serialPutchar (node->fd, 'a') ;
+  serialPutchar (node->fd, pin - node->pinBase) ;
+  vHi = serialGetchar (node->fd) ;
+  vLo = serialGetchar (node->fd) ;
+
+  return (vHi << 8) | vLo ;
+}
+
+
+/*
+ * myDigitalRead:
+ *********************************************************************************
+ */
+
+static int myDigitalRead (struct wiringPiNodeStruct *node, int pin)
+{
+  serialPutchar (node->fd, 'r') ; // Send read command
+  serialPutchar (node->fd, pin - node->pinBase) ;
+  return (serialGetchar (node->fd) == '0') ? 0 : 1 ;
+}
+
+
+/*
+ * drcSetup:
+ *	Create a new instance of an DRC GPIO interface.
+ *	Could be a variable nunber of pins here - we might not know in advance
+ *	if it's an ATmega with 14 pins, or something with less or more!
+ *********************************************************************************
+ */
+
+int drcSetupSerial (const int pinBase, const int numPins, const char *device, const int baud)
+{
+  int fd ;
+  int ok, tries ;
+  time_t then ;
+  struct wiringPiNodeStruct *node ;
+
+  if ((fd = serialOpen (device, baud)) < 0)
+    return wiringPiFailure (WPI_ALMOST, "Unable to open DRC device (%s): %s", device, strerror (errno)) ;
+
+  delay (10) ;	// May need longer if it's an Uno that reboots on the open...
+
+// Flush any pending input
+
+  while (serialDataAvail (fd))
+    (void)serialGetchar (fd) ;
+
+  ok = FALSE ;
+  for (tries = 1 ; (tries < 5) && (!ok) ; ++tries)
+  {
+    serialPutchar (fd, '@') ;		// Ping
+    then = time (NULL) + 2 ;
+    while (time (NULL) < then)
+      if (serialDataAvail (fd))
+      {
+        if (serialGetchar (fd) == '@')
+        {
+          ok = TRUE ;
+          break ;
+        }
+      }
+  }
+
+  if (!ok)
+  {
+    serialClose (fd) ;
+    return wiringPiFailure (WPI_FATAL, "Unable to communicate with DRC serial device") ;
+  }
+
+  node = wiringPiNewNode (pinBase, numPins) ;
+
+  node->fd              = fd ;
+  node->pinMode         = myPinMode ;
+  node->pullUpDnControl = myPullUpDnControl ;
+  node->analogRead      = myAnalogRead ;
+  node->digitalRead     = myDigitalRead ;
+  node->digitalWrite    = myDigitalWrite ;
+  node->pwmWrite        = myPwmWrite ;
+
+  return 0 ;
+}

wiringPi/drcSerial.h

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+/*
+ * drcSerial.h:
+ *	Extend wiringPi with the DRC Serial protocol (e.g. to Arduino)
+ *	Copyright (c) 2013 Gordon Henderson
+ ***********************************************************************
+ * 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 <http://www.gnu.org/licenses/>.
+ ***********************************************************************
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern int drcSetupSerial (const int pinBase, const int numPins, const char *device, const int baud) ;
+
+#ifdef __cplusplus
+}
+#endif