Kees Tijsen
Project for PWM synchronized by GPS
Dependencies: GPS MODSERIAL PowerControl mbed
Revision 0:bc3d86a76707, committed 2014-03-10
- Comitter:
- Deurklink
- Date:
- Mon Mar 10 15:09:21 2014 +0000
- Commit message:
- x
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/GPS.lib Mon Mar 10 15:09:21 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/Deurklink/code/GPS/#85068b8c3f50
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/MODSERIAL.lib Mon Mar 10 15:09:21 2014 +0000 @@ -0,0 +1,1 @@ +https://mbed.org/users/AjK/code/MODSERIAL/#ae0408ebdd68
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/PowerControl.lib Mon Mar 10 15:09:21 2014 +0000 @@ -0,0 +1,1 @@ +https://mbed.org/users/JST2011/code/PowerControl/#d0fa2aeb02a4
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Mon Mar 10 15:09:21 2014 +0000
@@ -0,0 +1,313 @@
+#include <mbed.h>
+#include "GPS.h"
+#include <string>
+#include "EthernetPowerControl.h"
+#include "MODSERIAL.h"
+
+#define XBEETIMEOUT 5
+
+//MODSERIAL pc(USBTX,USBRX);
+MODSERIAL XBee(p13,p14);
+char RxBuffer[256];
+bool PWMon = false;
+bool RxTO = false;
+
+GPS gps(p9,p10);
+
+
+int TimingOffset;
+int BeaconNumber;
+
+// Digital pins for setting the Timing offset
+DigitalIn T1(p11);
+DigitalIn T2(p12);
+DigitalIn T3(p15);
+DigitalIn T4(p16);
+DigitalIn T5(p17);
+DigitalIn T6(p18);
+DigitalIn T7(p19);
+DigitalIn T8(p20);
+
+// Digital pins for setting the beacon number
+DigitalIn B1(p24);
+DigitalIn B2(p23);
+DigitalIn B3(p22);
+DigitalIn B4(p21);
+
+// mBed LED 1
+DigitalOut L1(LED1);
+
+int PulseFrequency = 25; //Hz
+int Pulselength = 1000; //usec
+int PWMclock;
+int Period;
+
+InterruptIn PPS(p5);
+
+// PPS pin interrupt
+void ppsSync(){
+ // Toggle LED1
+ L1 = !L1;
+ if (PWMon == true){
+ // Reset PWM timer value so that new cycle immediately starts
+ LPC_PWM1->TC = Period;
+ }
+}
+
+Timeout _RxTimeOut;
+
+// XBee Receive Timeout
+void rxTimeOut(){
+ RxTO = true;
+}
+
+
+//------------------------------------DIP-SWITCHES---------------------------
+void readDipSwitch(){
+ // Transform the dip switch binary numbers into integers
+ // For the timing offset, the leftmost bit is the sign bit (2's complement)
+ TimingOffset = -128*T1 + 64*T2 + 32*T3 + 16*T4 + 8*T5 + 4*T6 + 2*T7 + T8;
+ BeaconNumber = 8*B1 + 4*B2 + 2*B3 + B4;
+}
+
+void initDipSwitch(){
+ // Set pull-down resistor for dip switch inputs
+ T1.mode(PullDown);
+ T2.mode(PullDown);
+ T3.mode(PullDown);
+ T4.mode(PullDown);
+ T5.mode(PullDown);
+ T6.mode(PullDown);
+ T7.mode(PullDown);
+ T8.mode(PullDown);
+
+ B1.mode(PullDown);
+ B2.mode(PullDown);
+ B3.mode(PullDown);
+ B4.mode(PullDown);
+}
+//---------------------------------------------------------------------------
+
+
+//------------------------------------PWM------------------------------------
+void startPWM(){
+ // enable PWM mode and counting
+ LPC_PWM1->TCR = (1 << 3) | 1;
+ PWMon = true;
+}
+
+void stopPWM(){
+ // Reset PWM-counter; this also stops it
+ LPC_PWM1->TCR = 2;
+ PWMon = false;
+}
+
+void resetPWM(int _PulseFrequency, int _Pulselength){
+ // Note: wherever you read pin P2.0, it is pin 2[0] of the microcontroller.
+ // This is wired to p26 of the mbed board.
+ stopPWM();
+ // First stop PWM if it is running
+
+ PWMclock = SystemCoreClock / 96;
+ Period = PWMclock / _PulseFrequency;
+
+
+ LPC_SC->PCONP |= 1 << 6;
+ // Reset mode PWM timer
+ LPC_PWM1->TCR = 2;
+
+ // configure P2.0 for PWM1.1 - O - Pulse Width Modulator 1, channel 1 output.
+ LPC_PINCON->PINSEL4 = (LPC_PINCON->PINSEL4 & ~(0x3 << 0)) | (0x1 << 0);
+
+ // Disable pullups for P2.0
+ LPC_PINCON->PINMODE4 = (LPC_PINCON->PINMODE4 & ~0x3) | 0x2;
+
+ // Set prescaler
+ //LPC_PWM1->PR = SystemCoreClock / (4 * 1000000) - 1;
+
+ // Set up match registers
+ LPC_PWM1->MR0 = Period*24+TimingOffset; // Set MR0 (Period)
+ /*
+ TimingOffset is there to compensate for crystal errors.
+ It has to be calculated for every mbed, as every crystal is a little different
+ It basically adds or detracts a few cycles from every period to keep the period equal for every module
+ */
+ LPC_PWM1->MR1 = _Pulselength*24; // Set MR1 (Pulse length)
+ LPC_PWM1->LER = 0x07; // set latch-enable register
+ LPC_PWM1->MCR |= 0x02; // Reset PWM1 on match
+ LPC_PWM1->PCR = 1 << 9; // enable PWM1 with single-edge operation
+}
+//------------------------------------/PWM------------------------------------
+
+
+
+//------------------------------------XBee------------------------------------
+
+void printStatus(){
+ // Print the status of a Beacon
+ XBee.printf("\r\n\nBeacon no.: %d; TimingOffset: %d",BeaconNumber, TimingOffset);
+ XBee.printf("\r\nLast GPS update: %d:%d:%2.2f",gps.hours, gps.minutes, gps.seconds);
+ XBee.printf("\r\nFlash frequency: %d Hz; Pulse length: %d usec", PulseFrequency, Pulselength);
+ XBee.printf("\r\nPulse generation: %d (0=off,1=on)",PWMon);
+ XBee.printf("\r\nGPS location: %f,%f", gps.latitude, gps.longitude);
+ XBee.printf("\r\nFixtype: %d (0=no fix,1=gps,2=differential)",gps.fixtype);
+ XBee.printf("\r\nNo. of satellites: %d",gps.satellites);
+}
+
+void getXBeeData(){
+ // Function used by parse data function
+ // Read data from the Xbee serial Buffer
+ // Wait until $ is read, then put characters received after that in RxBuffer[] until # is read.
+
+ RxTO = false; // Reset time-out
+ bool dollarSignRcv = false;
+ bool dashRcv = false;
+
+ _RxTimeOut.attach(&rxTimeOut,XBEETIMEOUT); // timeout after XBEETIMEOUT seconds
+
+ while(!dollarSignRcv){
+ // Read XBee until dollarsign received or timeout
+ if (XBee.readable()){
+ if (XBee.getc() == '$'){
+ dollarSignRcv = true;
+ //XBee.printf("$ received");
+ }
+ }
+ // Timeout if no $ is received within XBEETIMEOUT seconds
+ if (RxTO == true){
+ wait(BeaconNumber);
+ XBee.printf("\r\nBeacon %d rx time out",BeaconNumber);
+ return;
+ }
+ }
+
+ int i = 0;
+ while(!dashRcv){
+ // Fill buffer until dash is received, buffer is full or timeout
+ if (XBee.readable()){
+ RxBuffer[i] = XBee.getc();
+ if(RxBuffer[i] == '#') {
+ RxBuffer[i] = 0;
+ dashRcv = true;
+ //XBee.printf("# received");
+ }
+ i++;
+ }
+ // Return if buffer is full
+ if (i > 255){
+ wait(BeaconNumber);
+ XBee.printf("\r\nBeacon %d rx buffer overflow",BeaconNumber);
+ return;
+ }
+ // Timeout if no '#' is received within XBEETIMEOUT seconds
+ if (RxTO == true){
+ wait(BeaconNumber);
+ XBee.printf("\r\nBeacon %d rx time out",BeaconNumber);
+ XBee.printf("\r\nReceived: %s",RxBuffer);
+ return;
+ }
+ }
+}
+
+void parseXBee(){
+ // This function collects data from RxBuffer[] and reads it
+
+ // put data into RxBuffer[]
+ getXBeeData();
+ // $STATUS#
+ if (strncmp(RxBuffer, "STATUS",6) == 0){
+ wait(BeaconNumber);
+ printStatus();
+ }
+
+ // $STARTPULSE#
+ else if (strncmp(RxBuffer, "STARTPULSE",10) == 0){
+ // Only start PWM if GPS module has a fix
+ if (gps.fixtype > 0){
+ startPWM();
+ wait(BeaconNumber);
+ XBee.printf("\r\nBeacon %d pulses started",BeaconNumber);
+ }
+ else{
+ wait(BeaconNumber);
+ XBee.printf("\r\nBeacon %d has no GPS fix",BeaconNumber);
+ }
+ }
+
+ // $STOPPULSE#
+ else if (strncmp(RxBuffer, "STOPPULSE",10) == 0){
+ if (PWMon == true){
+ stopPWM();
+ wait(BeaconNumber);
+ XBee.printf("\r\nBeacon %d pulses stopped",BeaconNumber);
+ }
+ else{
+ wait(BeaconNumber);
+ XBee.printf("\r\nBeacon %d has not been started yet. No action",BeaconNumber);
+ }
+ }
+
+ // $CHANGEPULSE,freq(hz),pulselength(us)#
+ else if (strncmp(RxBuffer, "CHANGEPULSE",11) == 0){
+ if(sscanf(RxBuffer, "%*s %d %d", &PulseFrequency, &Pulselength) ==2){
+ resetPWM(PulseFrequency, Pulselength);
+ wait(BeaconNumber);
+ XBee.printf("\r\nBeacon %d frequency set to: %d Hz. Pulselength set to %d us",BeaconNumber,PulseFrequency,Pulselength);
+ XBee.printf("\r\nWaiting for start pulse command");
+ }
+ else{
+ wait(BeaconNumber);
+ XBee.printf("\r\nBeacon %d pulselength or frequency not received correctly, please try again (CHANGEPULSE,freq,pulselength)",BeaconNumber);
+ }
+ }
+ else{
+ wait(BeaconNumber);
+ XBee.printf("\r\nBeacon %d did not understand message",BeaconNumber);
+ XBee.printf("\r\nReceived: %s",RxBuffer);
+ }
+ // Flush buffer
+ for (int i=0;i<255;i++){
+ RxBuffer[i] = '0';
+ }
+}
+//-----------------------------------/XBee------------------------------------
+
+
+int main(void){
+ // Power down ethernet module
+ PHY_PowerDown();
+
+ // Initialize dipswitches
+ initDipSwitch();
+
+ // Read beacon number and timing offset
+ readDipSwitch();
+
+ // Set baud rate
+ XBee.baud(9600);
+
+ XBee.printf("\r\n.. Beacon %d Initializing ..\n",BeaconNumber);
+
+ // Initialize GPS unit
+ gps.Init();
+
+ //Attach interrupt to rising edge of GPS PPS pin
+ PPS.rise(&ppsSync);
+
+ // Initialize PWM
+ resetPWM(PulseFrequency, Pulselength);
+
+ //pc.printf("\r\n.. Beacon %d Initialization finished ..\n",BeaconNumber);
+ XBee.printf("\r\n.. Beacon %d Initialization finished ..\n",BeaconNumber);
+
+ while(1){
+ // Parse GPS data until data is received on XBee serial port
+
+ if (XBee.readable()){
+ parseXBee();
+ }
+ gps.parseData();
+ readDipSwitch();
+
+ }
+}
\ No newline at end of file
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Mon Mar 10 15:09:21 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/824293ae5e43 \ No newline at end of file