fl@c@ Johnson / Mbed 2 deprecated ramanSpectrometer_imagingBoard Featured

This is the device firmware for the imagingBoard on the DIY 3D Printable Raspberry Pi Raman Spectrometer. For more details please visit: http://hackaday.io/project/1279

Dependencies:   mbed

main.cpp@0:984447b91a04, 2014-08-15 (annotated)

Committer:
flatcat
Date:
Fri Aug 15 10:35:34 2014 +0000
Revision:
0:984447b91a04
Child:
1:a220fd937508
http://hackaday.io/project/1279

Who changed what in which revision?

UserRevisionLine numberNew contents of line
flatcat 0:984447b91a04 1 #include "mbed.h"
flatcat 0:984447b91a04 2
flatcat 0:984447b91a04 3 // *** BE SURE TO TEST BEFORE AND AFTER FOR 'IDLING'... CLEAR THE CCD EVERY OTHER FRAME TO TRY AND ELIMINATE NOISE BUILDUP
flatcat 0:984447b91a04 4 //From http://www.ing.iac.es/~docs/ins/das/ins-das-29/integration.html
flatcat 0:984447b91a04 5 //"Idling" vs. integrating
flatcat 0:984447b91a04 6 //Charge from light leaks and thermal noise builds up on the detector between observations. If this charge is integrated by the detector, it may not be completely
flatcat 0:984447b91a04 7 //cleared away by the clear cycle of the next observation. In that case, the observation will be contaminated by extra counts. (Often, this appears as a ramp in the
flatcat 0:984447b91a04 8 //background leading up to a saturated region in the low-numbered rows.)
flatcat 0:984447b91a04 9 //To avoid this problem, the detector is made to clear itself continuously between observations. This is called "idling", and is reported as such on the mimic.
flatcat 0:984447b91a04 10
flatcat 0:984447b91a04 11 PwmOut shiftGate(PB_8);
flatcat 0:984447b91a04 12 PwmOut icg(PB_3);
flatcat 0:984447b91a04 13 PwmOut masterClock(PB_4);
flatcat 0:984447b91a04 14 AnalogIn imageIn(A0);
flatcat 0:984447b91a04 15 AnalogOut imageOut(A5);
flatcat 0:984447b91a04 16 DigitalOut myled(LED1);
flatcat 0:984447b91a04 17 Serial raspi(USBTX, USBRX);
flatcat 0:984447b91a04 18
flatcat 0:984447b91a04 19 int masterFreq_period = 2; //microseconds
flatcat 0:984447b91a04 20 int masterFreq_width = 1; //microseconds
flatcat 0:984447b91a04 21 int icgFreq_period = 500000; //microseconds
flatcat 0:984447b91a04 22 int icgFreq_width = 250000; //microseconds <------------- LOWER THIS NUMBER TO INCREASE SENSITIVITY
flatcat 0:984447b91a04 23 int shiftGate_delay = 287; //microseconds
flatcat 0:984447b91a04 24 int shiftGate_period = 200; //microseconds
flatcat 0:984447b91a04 25 int shiftGate_width = 100; //microseconds
flatcat 0:984447b91a04 26
flatcat 0:984447b91a04 27 #define MV(x) ((0xFFF*x)/3300)
flatcat 0:984447b91a04 28
flatcat 0:984447b91a04 29 int main()
flatcat 0:984447b91a04 30 {
flatcat 0:984447b91a04 31 // set the masterClock
flatcat 0:984447b91a04 32 masterClock.period_us(masterFreq_period);
flatcat 0:984447b91a04 33 masterClock.pulsewidth_us(masterFreq_width);
flatcat 0:984447b91a04 34
flatcat 0:984447b91a04 35 // set the ICG clock and have it start 82.76ms after the shiftGate - this will sync the clocks up so the ICQ is going low slightly before the shiftGate is going high
flatcat 0:984447b91a04 36 icg.period_us(icgFreq_period);
flatcat 0:984447b91a04 37 icg.pulsewidth_us(icgFreq_width); // <------------- LOWER THIS NUMBER TO INCREASE SENSITIVITY
flatcat 0:984447b91a04 38
flatcat 0:984447b91a04 39 // set the shiftGate and have it start 15us after the masterClock - this will sync the clocks up so the shiftGate is going high just as a clock cycle is going high
flatcat 0:984447b91a04 40 wait_us(shiftGate_delay);
flatcat 0:984447b91a04 41 shiftGate.period_us(shiftGate_period);
flatcat 0:984447b91a04 42 shiftGate.pulsewidth_us(shiftGate_width);
flatcat 0:984447b91a04 43
flatcat 0:984447b91a04 44 raspi.baud(921600);
flatcat 0:984447b91a04 45 // do something while it's having fun..
flatcat 0:984447b91a04 46 while(1) {
flatcat 0:984447b91a04 47 // wait(.0001);
flatcat 0:984447b91a04 48 // uint16_t meas = imageIn.read_u16();
flatcat 0:984447b91a04 49 // if (meas < MV(1000)) {
flatcat 0:984447b91a04 50 // myled = 1;
flatcat 0:984447b91a04 51 // printf("BINGO: %d \r\n", meas);
flatcat 0:984447b91a04 52 // }
flatcat 0:984447b91a04 53 // myled = 0;
flatcat 0:984447b91a04 54 imageOut.write(imageIn.read());
flatcat 0:984447b91a04 55 }
flatcat 0:984447b91a04 56 }
flatcat 0:984447b91a04 57