Part Number: TMS320F280039C
Hello,
I have a weird problem. I have one project that reads perfect values from ADC A, B, and C. Then I have another project with what looks like the same init code that reads ADCA perfectly, but ADC B and C are wrong by as much as 30 counts in some places.
I've used Beyond Compare to compare the initialization between the 2 projects, is there anything that comes to mind I should check that could cause this?
Init code:
void Setup_FastADC()
{
// Select interrupt source - this will be the last sample converted and therefore trigger the interrupt 1
ADC_setInterruptSource(ADCC_BASE, ADC_INT_NUMBER1, ADC_DCBUS_SOCNUM);
// Setup ADCs for PhA - this is triggered based off of counter EPWM1 SOCA (setup below)
// Sample window must be > 75ns per datasheet, > 90ns for AGPIO per datasheet (at least > 11 SYSCLK cycles to be safe - 91.3ns)
// Sample window must also be as long as 1 ADC clock cycle (40ns) - input sample window in SysClk cycles (11 cycle = 91.3ns)
ADC_setupSOC(ADC_PHA_I_BASE, ADC_PHA_I_SOCNUM, ADC_TRIGGER_EPWM1_SOCA, ADC_PHA_I_CHANNEL, ADC_SAMPLE_WINDOW);
ADC_setInterruptSOCTrigger(ADC_PHA_I_BASE, ADC_PHA_I_SOCNUM, ADC_INT_SOC_TRIGGER_NONE);
// Setup ADCs for PhB - this is triggered based off of counter EPWM1 SOCA (setup below)
// Sample window must be > 75ns per datasheet, > 90ns for AGPIO per datasheet (at least > 11 SYSCLK cycles to be safe - 91.3ns)
// Sample window must also be as long as 1 ADC clock cycle (40ns) - input sample window in SysClk cycles (11 cycle = 91.3ns)
ADC_setupSOC(ADC_PHB_I_BASE, ADC_PHB_I_SOCNUM, ADC_TRIGGER_EPWM1_SOCA, ADC_PHB_I_CHANNEL, ADC_SAMPLE_WINDOW);
ADC_setInterruptSOCTrigger(ADC_PHB_I_BASE, ADC_PHB_I_SOCNUM, ADC_INT_SOC_TRIGGER_NONE);
// Setup ADCs for PhC - this is triggered based off of counter EPWM1 SOCA (setup below)
// Sample window must be > 75ns per datasheet, > 90ns for AGPIO per datasheet (at least > 11 SYSCLK cycles to be safe - 91.3ns)
// Sample window must also be as long as 1 ADC clock cycle (40ns) - input sample window in SysClk cycles (11 cycle = 91.3ns)
ADC_setupSOC(ADC_PHC_I_BASE, ADC_PHC_I_SOCNUM, ADC_TRIGGER_EPWM1_SOCA, ADC_PHC_I_CHANNEL, ADC_SAMPLE_WINDOW);
ADC_setInterruptSOCTrigger(ADC_PHC_I_BASE, ADC_PHC_I_SOCNUM, ADC_INT_SOC_TRIGGER_NONE);
// If we need any more PBB's we can copy them from above
// Setup DCLink sampling -> This will trigger interrupt
ADC_setupSOC(ADC_DCBUS_BASE, ADC_DCBUS_SOCNUM, ADC_TRIGGER_EPWM1_SOCA, ADC_DCBUS_CHANNEL, ADC_SAMPLE_WINDOW);
ADC_setInterruptSOCTrigger(ADC_DCBUS_BASE, ADC_DCBUS_SOCNUM, ADC_INT_SOC_TRIGGER_NONE);
}
void Init_ADC()
{
// asysctl initialization
// Disables the temperature sensor output to the ADC.
ASysCtl_disableTemperatureSensor();
// Set the analog voltage reference selection to internal.
ASysCtl_setAnalogReferenceInternal( ASYSCTL_VREFHI );
// Set the internal analog voltage reference selection to 1.65V.
ASysCtl_setAnalogReference1P65( ASYSCTL_VREFHI );
// Setup ADC
// Three ADC modules in this device
// initialize the ADC handles
adcHandle[0] = ADCA_BASE;
adcHandle[1] = ADCB_BASE;
adcHandle[2] = ADCC_BASE;
// initialize the ADC results
adcResult[0] = ADCARESULT_BASE;
adcResult[1] = ADCBRESULT_BASE;
adcResult[2] = ADCCRESULT_BASE;
// Set ADC voltage ref
ADC_setVREF(adcHandle[0], ADC_REFERENCE_EXTERNAL, ADC_REFERENCE_3_3V);
ADC_setVREF(adcHandle[1], ADC_REFERENCE_EXTERNAL, ADC_REFERENCE_3_3V);
ADC_setVREF(adcHandle[2], ADC_REFERENCE_EXTERNAL, ADC_REFERENCE_3_3V);
// Set main clock scaling factor (60MHz max clock for the ADC module)
// ADC clock set up for 30 MHz
ADC_setPrescaler(adcHandle[0], ADC_CLK_DIV_2_0);
ADC_setPrescaler(adcHandle[1], ADC_CLK_DIV_2_0);
ADC_setPrescaler(adcHandle[2], ADC_CLK_DIV_2_0);
// Set the ADC interrupt pulse generation to end of conversion
ADC_setInterruptPulseMode(adcHandle[0], ADC_PULSE_END_OF_CONV);
ADC_setInterruptPulseMode(adcHandle[1], ADC_PULSE_END_OF_CONV);
ADC_setInterruptPulseMode(adcHandle[2], ADC_PULSE_END_OF_CONV);
// Disables SOC burst mode.
ADC_disableBurstMode(adcHandle[0]);
ADC_disableBurstMode(adcHandle[1]);
ADC_disableBurstMode(adcHandle[2]);
// Set priority of SOCs
ADC_setSOCPriority(adcHandle[0], ADC_PRI_ALL_HIPRI);
ADC_setSOCPriority(adcHandle[1], ADC_PRI_ALL_HIPRI);
ADC_setSOCPriority(adcHandle[2], ADC_PRI_ALL_HIPRI);
// Enable ADCs
ADC_enableConverter(adcHandle[0]);
ADC_enableConverter(adcHandle[1]);
ADC_enableConverter(adcHandle[2]);
// Delay to allow ADCs to power up
SysCtl_delay(5000U);
// Setup ADCs for fast samples - A, B, C, DC Link
Setup_FastADC();
// Init motor PWM to trigger ADC
MotorPWM_Init();
// Enable ADC interrupt - Enables ADC interrupts in group 1 - priority 12
// Kicks off the fast thread
Interrupt_clearACKGroup(INTERRUPT_ACK_GROUP1);
Interrupt_register(INT_ADCC1, &adcC1ISR); // register ISR
}
void Enable_ADCInt()
{
// Enable fast thread interrupt
Interrupt_enable(INT_ADCC1);
// Enable user mux interrupts
Interrupt_enable(INT_ADCA2);
Interrupt_enable(INT_ADCB2);
Interrupt_enable(INT_ADCC2);
Interrupt_register(INT_ADCA2, &adcA2ISR); // register ISR
Interrupt_register(INT_ADCB2, &adcB2ISR); // register ISR
Interrupt_register(INT_ADCC2, &adcC2ISR); // register ISR
// Enable fast thread ADC interrupt
ADC_enableInterrupt(ADCC_BASE, ADC_INT_NUMBER1);
ADC_clearInterruptStatus(ADCC_BASE, ADC_INT_NUMBER1);
ADC_disableContinuousMode(ADCC_BASE, ADC_INT_NUMBER1);
}
Thanks for the help!
