Brain Trust / Mbed 2 deprecated digipot_Debug

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Dependencies:   mbed

Fork of digipot by Erik Golabek

digipot.cpp@0:57bdd27601ad, 2015-04-03 (annotated)

Committer:
Braintrust
Date:
Fri Apr 03 20:04:16 2015 +0000
Revision:
0:57bdd27601ad
Child:
1:0b0025664bb7
Final, With debugging code included

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Braintrust 0:57bdd27601ad 1 //Digipot code with 2nd CAN Transceiver for testing
Braintrust 0:57bdd27601ad 2
Braintrust 0:57bdd27601ad 3 #include "mbed.h"
Braintrust 0:57bdd27601ad 4
Braintrust 0:57bdd27601ad 5 static int id = 0x04; //Module CAN ID, to be assigned by keypad team.
Braintrust 0:57bdd27601ad 6 static double input_amp = 3.3; //input analog signal is 3.3V
Braintrust 0:57bdd27601ad 7
Braintrust 0:57bdd27601ad 8 static double R1 = 10; //Opamp resistor between output and inverting-input
Braintrust 0:57bdd27601ad 9 static double R2 = 5.6; //Opamp resistor between inverting-input and ground
Braintrust 0:57bdd27601ad 10 static double gain = 1 + R2/R1; //Non-inverting opamp gain
Braintrust 0:57bdd27601ad 11
Braintrust 0:57bdd27601ad 12 //Debugging Variables
Braintrust 0:57bdd27601ad 13 DigitalOut led1(LED1); //debugging LED1
Braintrust 0:57bdd27601ad 14 Ticker ticker; //triggers debugging send
Braintrust 0:57bdd27601ad 15 char counter = 0; //Output amplitude
Braintrust 0:57bdd27601ad 16 CAN can2(p30, p29); //2nd debugging send transceiver
Braintrust 0:57bdd27601ad 17
Braintrust 0:57bdd27601ad 18 //Values to be used in final implementation
Braintrust 0:57bdd27601ad 19 DigitalOut led2(LED2); //debugging LED2
Braintrust 0:57bdd27601ad 20 DigitalOut CS(p8); // inverted chip select
Braintrust 0:57bdd27601ad 21 SPI spi(p5, p6, p7); // mosi, miso, sclk
Braintrust 0:57bdd27601ad 22 CAN can1(p9, p10); //reading transceiver
Braintrust 0:57bdd27601ad 23
Braintrust 0:57bdd27601ad 24
Braintrust 0:57bdd27601ad 25 void digipot (int OutputAmp)
Braintrust 0:57bdd27601ad 26 {
Braintrust 0:57bdd27601ad 27 CS=0; // Deselects the digipot
Braintrust 0:57bdd27601ad 28 // Setup the spi for 8 bit data, high steady state clock,
Braintrust 0:57bdd27601ad 29 // second edge capture, with a 1MHz clock rate
Braintrust 0:57bdd27601ad 30 spi.format(8,3);
Braintrust 0:57bdd27601ad 31 spi.frequency(1000000);
Braintrust 0:57bdd27601ad 32
Braintrust 0:57bdd27601ad 33 uint8_t wiper = uint8_t(OutputAmp*(255/(input_amp * gain))); //Generates appropriate Wiper position
Braintrust 0:57bdd27601ad 34
Braintrust 0:57bdd27601ad 35 spi.write(0x11); // Write data command, potentiometer zero
Braintrust 0:57bdd27601ad 36 spi.write(wiper); // Writes wiper value
Braintrust 0:57bdd27601ad 37
Braintrust 0:57bdd27601ad 38 CS=1; // Selects the digipot, and executes command
Braintrust 0:57bdd27601ad 39 }
Braintrust 0:57bdd27601ad 40
Braintrust 0:57bdd27601ad 41 void send() //For debugging
Braintrust 0:57bdd27601ad 42 {
Braintrust 0:57bdd27601ad 43 if(can2.write(CANMessage(id, &counter, 1))) {
Braintrust 0:57bdd27601ad 44 counter++;
Braintrust 0:57bdd27601ad 45 if(counter ==6)
Braintrust 0:57bdd27601ad 46 {
Braintrust 0:57bdd27601ad 47 counter = 0; //reset counter
Braintrust 0:57bdd27601ad 48 }
Braintrust 0:57bdd27601ad 49 }
Braintrust 0:57bdd27601ad 50 led1 = !led1;
Braintrust 0:57bdd27601ad 51 }
Braintrust 0:57bdd27601ad 52
Braintrust 0:57bdd27601ad 53 int main()
Braintrust 0:57bdd27601ad 54 {
Braintrust 0:57bdd27601ad 55 ticker.attach(&send,10); //Debugging: Changes output amplitude every 10 seconds
Braintrust 0:57bdd27601ad 56
Braintrust 0:57bdd27601ad 57 int OutputAmp = 0; //Default output amplitude value
Braintrust 0:57bdd27601ad 58 digipot(OutputAmp);
Braintrust 0:57bdd27601ad 59
Braintrust 0:57bdd27601ad 60 CANMessage msg;
Braintrust 0:57bdd27601ad 61
Braintrust 0:57bdd27601ad 62 while(1)
Braintrust 0:57bdd27601ad 63 {
Braintrust 0:57bdd27601ad 64 if(can1.read(msg) && msg.id == id)
Braintrust 0:57bdd27601ad 65 {
Braintrust 0:57bdd27601ad 66 OutputAmp = msg.data[0]; //Input is an int 0,1,2,3,4,5
Braintrust 0:57bdd27601ad 67 digipot(OutputAmp); //set digipot value
Braintrust 0:57bdd27601ad 68 led2 = !led2;
Braintrust 0:57bdd27601ad 69 }
Braintrust 0:57bdd27601ad 70 }
Braintrust 0:57bdd27601ad 71 }