Diff: main.cpp

Revision:

0:dfbf890fb03a

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Sep 02 06:56:13 2016 +0000
@@ -0,0 +1,184 @@
+#include "mbed.h"
+#include "USBSerial.h"
+
+USBSerial pc;
+
+DigitalOut ASIC_CS(P0_2);
+DigitalOut DAC_CS(P1_26);
+DigitalOut DAC_LDAC(P1_14);
+DigitalOut DAC_SHDN(P1_15);
+DigitalInOut PD_CHA(P0_21);
+
+
+AnalogIn DAC_OUT_A(P0_11);
+AnalogIn DAC_OUT_B(P0_12);
+AnalogIn OUT_N(P0_13);
+AnalogIn OUT_P(P0_14);
+AnalogIn BG_BUF(P0_15);
+AnalogIn PHOTO_DIODE(P0_22);
+
+PwmOut SWITCH(P1_24); // shorts the op-amp feedback network when high 24
+//PwmOut EXTCLK(P1_25); // can be used to apply an external clock to the ASIC if needed (need to solder to P0_20 (if actually required) due to mistake)
+
+SPI ASIC(P0_9, P0_8, P1_29);//MOSI, MISO, SCLK
+SPI DAC(P1_22, P1_21, P1_20);// MOSI, MISO, SCLK
+
+int ASIC_SPI_REGISTER;
+char command, p1, p2, p3, p4;
+void variable_defaults()
+{
+   ASIC_SPI_REGISTER = (0x0000);
+   ASIC_CS=1;
+   DAC_CS=1;
+   DAC_LDAC=0;
+   DAC_SHDN=0; //Disable DAC
+   PD_CHA.input();
+   PD_CHA.mode(PullNone);
+}
+
+void connect_PD_CHA(int value)//connect power down and drive to value
+{
+   PD_CHA.output();
+   PD_CHA = value; 
+}
+
+void disable_DAC()
+{
+    DAC_SHDN=0;
+}
+
+void disconnect_PD_CHA()
+{
+   PD_CHA.input();
+   PD_CHA.mode(PullNone);
+}
+
+int Set_DAC_A(int desired_value_A) // sets the value of MCP4922 DAC channel A
+{
+       // int desired_value_A = (voutA/3.3)*4096;
+       DAC_SHDN=1; //Enable DAC
+        char command_register_msb = (0x70);// 01110000 for DAC A, BUF, Gain =1  and no shutdown
+        command_register_msb = ((command_register_msb)|desired_value_A>>8); // assign first 4 bits to first byte to send
+        char command_register_lsb = desired_value_A; // assign last 8 bits to second byte to send
+        DAC_CS =0; // bring CS low
+        int junk= DAC.write(command_register_msb); // write first byte
+        junk= DAC.write(command_register_lsb); // write second byte
+        DAC_CS=1;                               // De-select device 
+        return 1;
+}
+
+int Set_DAC_B(int desired_value_B) // sets the value of MCP4922 DAC channel B
+{
+       // int desired_value_B = (voutB/3.3)*4096;
+       DAC_SHDN=1; //Enable DAC
+        char command_register_msb = (0xF0);// 11110000 for DAC B, BUF, Gain =1  and no shutdown
+        command_register_msb = ((command_register_msb)|desired_value_B>>8); // assign first 4 bits to first byte to send
+        char command_register_lsb = desired_value_B; // assign last 8 bits to second byte to send
+        DAC_CS =0; // bring CS low
+        int junk= DAC.write(command_register_msb); // write first byte
+        junk= DAC.write(command_register_lsb); // write second byte
+        DAC_CS=1;                               // De-select device 
+        return 1;
+}
+
+void Send_ASIC_SPI(char to_send)
+{
+    ASIC_CS=0;
+    int junk = ASIC.write(to_send);
+    ASIC_CS=1;
+}
+
+void ExternalClock(float duty_cycle, int period_us)
+{
+    //EXTCLK.write(duty_cycle);
+   // EXTCLK.period_us(period_us);
+}
+
+void SWITCH_SET(float duty_cycle, int period_us)
+{
+    SWITCH.write(duty_cycle);
+    SWITCH.period_us(period_us);
+}
+
+int main() {
+    variable_defaults();
+    Set_DAC_A(0);
+    Set_DAC_B(0);
+    ExternalClock(0.0, 1000);
+    SWITCH_SET(10,255);
+    ASIC.format(8, 1);// the ASIC should operate in SPI mode 1
+  //  PHOTODIODE.mode(PullNone);
+    while(1) {
+        if (pc.readable()){
+        command = pc.getc();   // Data from PC (command)
+        p1 = pc.getc();   // Data from PC (param p1)
+        p2 = pc.getc();   // Data from PC (param p2)
+        p3 = pc.getc();   // Data from PC (param p2)
+        p4 = pc.getc();   // Data from PC (param p2)
+        int scrap = pc.getc();    // Carriage Return
+
+        if (command=='A') // update ASIC SPI REGISTER
+        {
+         ASIC_SPI_REGISTER=0x0000; //clear register
+         ASIC_SPI_REGISTER = ASIC_SPI_REGISTER|p2<<16;
+         ASIC_SPI_REGISTER = ASIC_SPI_REGISTER|p3<<8;
+         ASIC_SPI_REGISTER = ASIC_SPI_REGISTER|p4;
+         Send_ASIC_SPI((p2));
+         Send_ASIC_SPI((p3));
+         Send_ASIC_SPI((p4));
+        // pc.printf("%d\n",ASIC_SPI_REGISTER);
+        // pc.printf("%d\n",0xff&(ASIC_SPI_REGISTER>>16));
+        // pc.printf("%d\n",0xff&(ASIC_SPI_REGISTER>>8));
+        // pc.printf("%d\n",0xff&(ASIC_SPI_REGISTER));
+        }
+        else if (command=='a') // set vouta of DAC
+        {
+        int desired_value = ((0x0f)&p3)<<8;
+        desired_value = desired_value|p4;    
+        Set_DAC_A(desired_value);
+       // pc.printf("%d\n",desired_value);
+        }
+        else if (command=='b') // set voutb of DAC
+        {
+        int desired_value = ((0x0f)&p3)<<8;
+        desired_value = desired_value|p4;    
+        Set_DAC_B(desired_value);
+        }
+        else if(command=='C')// read all analog inputs
+        {
+        pc.printf("%f,%f,%f,%f,%f,%f\n", DAC_OUT_A.read(), DAC_OUT_B.read(), OUT_N.read(), OUT_P.read(), BG_BUF.read(), PHOTO_DIODE.read());
+        }
+        else if(command=='K')// set external clock
+        {
+        //   float duty_cycle = (float)p3/ (float)256; // duty cycle
+        //  int period_us = p4; //period in microseconds    
+        //  ExternalClock(duty_cycle, period_us);
+        // pc.printf("%f, %d, %d, %d, %d, %d\n", duty_cycle, period_us, p1, p2, p3, p4);
+        }
+        else if(command=='S')// set switching settings
+        {
+        float duty_cycle = (float)p3/ (float)256; // duty cycle
+        int period_us = p4; //period in microseconds    
+        SWITCH_SET(duty_cycle, period_us);
+       // pc.printf("%f, %d\n", duty_cycle, period_us);
+       // pc.printf("%f, %d, %d, %d, %d, %d\n", duty_cycle, period_us, p1, p2, p3, p4);
+        }        
+        else if(command=='P')
+        {
+            connect_PD_CHA(1);
+        }
+        else if(command=='p')
+        {
+            connect_PD_CHA(0);
+        }
+        else if(command=='O')
+        {
+            disconnect_PD_CHA();
+        }
+        else if(command=='d')
+        {
+          disable_DAC();  
+        }     
+      }  
+    }
+}