Part Number: TMS320F28379D
Tool/software: Code Composer Studio
Dear TI Hello,
I am working on the ADC Post processing block offset example,
I want to experiment the PPB, I get started from the TI example in c2000 folder,
I have encountered a small problem related to the protection macros EALLOW and EDIS. However, the ADCPPB1OFFCAL.all registers are not set with the value I want to sub from the measured value.
I added the EALLOW and EDIS macros to TI code and ADCPPB1OFFCAL get set. In my application I have a HW offset of 10, => the ADCPPB1OFFCAL = 10. For test purposes, I used the SetupPPBOffset function to subtract manually an offset to the two ADCs measured value.
In the debug session:
AdcaResult unsigned int 1069 0x0000A9C9@Data
AdcaResult_offsetAdjusted unsigned int 868 0x0000A9C8@Data
AdcbResult unsigned int 1053 0x0000A9C6@Data
AdcbResult_offsetAdjusted unsigned int 859 0x0000A9C7@Data
AdcaResultRegs ADC RESULT Registers
ADCRESULT0 1069 (Decimal) ADC Result 0 Register [Memory Mapped]
ADCRESULT1 868 (Decimal) ADC Result 1 Register [Memory Mapped]
ADCPPB1OFFCAL 10 (Decimal) ADC PPB1 Offset Calibration Register [Memory Mapped]
The difference between the ADCRESULT0 and ADCRESULT1 is more than 10?
am I missing something?
Thank you in advance,
Regards,
S.Tarik,
//###########################################################################
//
// FILE: adc_ppb_offset_cpu01.c
//
// TITLE: ADC offset adjust using post-processing block for F2837xD.
//
//! \addtogroup cpu01_example_list
//! <h1> ADC PPB Offset (adc_ppb_offset)</h1>
//!
//! This example software triggers the ADC. Some SOCs have automatic offset
//! adjustment applied by the post-processing block.
//!
//! After the program runs, the memory will contain:\n
//!
//! - \b AdcaResult \b: a digital representation of the voltage on pin A0
//! - \b AdcaResult_offsetAdjusted \b : a digital representation of the voltage
//! on pin A0, plus 100 LSBs of automatically added offset
//! - \b AdcbResult \b: a digital representation of the voltage on pin B0
//! - \b AdcbResult_offsetAdjusted \b : a digital representation of the voltage
//! on pin B0 minus 100 LSBs of automatically added offset
//
//###########################################################################
// $TI Release: F2837xD Support Library v3.06.00.00 $
// $Release Date: Mon May 27 06:48:24 CDT 2019 $
// $Copyright:
// Copyright (C) 2013-2019 Texas Instruments Incorporated - http://www.ti.com/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the
// distribution.
//
// Neither the name of Texas Instruments Incorporated nor the names of
// its contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// $
//###########################################################################
//
// Included Files
//
#include "F28x_Project.h"
//
// Function Prototypes
//
void ConfigureADC(void);
void SetupADCSoftware(Uint16 channel);
void SetupPPBOffset(Uint16 aOffset, Uint16 bOffset);
//
// Globals
//
Uint16 AdcaResult;
Uint16 AdcaResult_offsetAdjusted;
Uint16 AdcbResult;
Uint16 AdcbResult_offsetAdjusted;
void main(void)
{
Uint16 adcChannelId;
//
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the F2837xD_SysCtrl.c file.
//
InitSysCtrl();
//
// Step 2. Initialize GPIO:
// This example function is found in the F2837xD_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
//
InitGpio();
//
// Step 3. Clear all interrupts and initialize PIE vector table:
// Disable CPU interrupts
//
DINT;
//
// Initialize the PIE control registers to their default state.
// The default state is all PIE interrupts disabled and flags
// are cleared.
// This function is found in the F2837xD_PieCtrl.c file.
//
InitPieCtrl();
//
// Disable CPU interrupts and clear all CPU interrupt flags:
//
IER = 0x0000;
IFR = 0x0000;
//
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example. This is useful for debug purposes.
// The shell ISR routines are found in F2837xD_DefaultIsr.c.
// This function is found in F2837xD_PieVect.c.
//
InitPieVectTable();
//
// Enable global Interrupts and higher priority real-time debug events:
//
EINT; // Enable Global interrupt INTM
ERTM; // Enable Global realtime interrupt DBGM
//
//Configure the ADCs and power them up
//
ConfigureADC();
//
//Setup the ADCs for software conversions
//
adcChannelId = ADC_CHANNEL_2;
SetupADCSoftware(adcChannelId);
//
//Setup PPB offset correction
//conversion on channel A will subtract 100
//conversion on channel B will add 100
//
SetupPPBOffset(10, 10);
//
//take conversions indefinitely in loop
//
do
{
//
//convert, wait for completion, and store results
//start conversions immediately via software, ADCA
//
AdcaRegs.ADCSOCFRC1.all = 0x0003; //SOC0 and SOC1
//
//start conversions immediately via software, ADCB
//
AdcbRegs.ADCSOCFRC1.all = 0x0003; //SOC0 and SOC1
//
//wait for ADCA to complete, then acknowledge flag
//
while(AdcaRegs.ADCINTFLG.bit.ADCINT1 == 0);
AdcaRegs.ADCINTFLGCLR.bit.ADCINT1 = 1;
//
//wait for ADCB to complete, then acknowledge flag
//
while(AdcbRegs.ADCINTFLG.bit.ADCINT1 == 0);
AdcbRegs.ADCINTFLGCLR.bit.ADCINT1 = 1;
//
//store results
//
AdcaResult = AdcaResultRegs.ADCRESULT0;
AdcaResult_offsetAdjusted = AdcaResultRegs.ADCRESULT1;
AdcbResult = AdcbResultRegs.ADCRESULT0;
AdcbResult_offsetAdjusted = AdcbResultRegs.ADCRESULT1;
//
//software breakpoint, hit run again to get updated conversions
//
asm(" ESTOP0");
}while(1);
}
//
// ConfigureADC - Write ADC configurations and power up the ADC for both
// ADC A and ADC B
//
void ConfigureADC(void)
{
EALLOW;
//
//write configurations
//
AdcaRegs.ADCCTL2.bit.PRESCALE = 6; //set ADCCLK divider to /4
AdcbRegs.ADCCTL2.bit.PRESCALE = 6; //set ADCCLK divider to /4
AdcSetMode(ADC_ADCA, ADC_RESOLUTION_12BIT, ADC_SIGNALMODE_SINGLE);
AdcSetMode(ADC_ADCB, ADC_RESOLUTION_12BIT, ADC_SIGNALMODE_SINGLE);
//
//Set pulse positions to late
//
AdcaRegs.ADCCTL1.bit.INTPULSEPOS = 1;
AdcbRegs.ADCCTL1.bit.INTPULSEPOS = 1;
//
//power up the ADCs
//
AdcaRegs.ADCCTL1.bit.ADCPWDNZ = 1;
AdcbRegs.ADCCTL1.bit.ADCPWDNZ = 1;
//
//delay for 1ms to allow ADC time to power up
//
DELAY_US(1000);
EDIS;
}
//
// SetupADCSoftware - Configure ADC SOC and acquisition window
//
void SetupADCSoftware(Uint16 channel)
{
Uint16 acqps;
//
// Determine minimum acquisition window (in SYSCLKS) based on resolution
//
if(ADC_RESOLUTION_12BIT == AdcaRegs.ADCCTL2.bit.RESOLUTION)
{
acqps = 14; //75ns
}
else //resolution is 16-bit
{
acqps = 63; //320ns
}
//
//Select the channels to convert and end of conversion flag
//ADCA
//
EALLOW;
AdcaRegs.ADCSOC0CTL.bit.CHSEL = channel; // ADC Channel to be converted on SOC0 trigger
AdcaRegs.ADCSOC0CTL.bit.ACQPS = acqps; // sample window is 100 SYSCLK cycles
AdcaRegs.ADCSOC1CTL.bit.CHSEL = channel; // ADC Channel to be converted on SOC1 trigger
AdcaRegs.ADCSOC1CTL.bit.ACQPS = acqps; // sample window is 100 SYSCLK cycles
AdcaRegs.ADCINTSEL1N2.bit.INT1SEL = 1; // end of SOC1 will set INT1 flag
AdcaRegs.ADCINTSEL1N2.bit.INT1E = 1; // enable INT1 flag
AdcaRegs.ADCINTFLGCLR.bit.ADCINT1 = 1; // make sure INT1 flag is cleared
//
//ADCB
//
AdcbRegs.ADCSOC0CTL.bit.CHSEL = channel; // ADC Channel to be converted on SOC0 trigger
AdcbRegs.ADCSOC0CTL.bit.ACQPS = acqps; // sample window is 100 SYSCLK cycles
AdcbRegs.ADCSOC1CTL.bit.CHSEL = channel; // ADC Channel to be converted on SOC1 trigger
AdcbRegs.ADCSOC1CTL.bit.ACQPS = acqps; // sample window is 100 SYSCLK cycles
AdcbRegs.ADCINTSEL1N2.bit.INT1SEL = 1; // end of SOC1 will set INT1 flag
AdcbRegs.ADCINTSEL1N2.bit.INT1E = 1; // enable INT1 flag
AdcbRegs.ADCINTFLGCLR.bit.ADCINT1 = 1; // make sure INT1 flag is cleared
EDIS;
}
//
// SetupPPBOffset - Configure PPB for SOC
//
void SetupPPBOffset(Uint16 aOffset, Uint16 bOffset)
{
EALLOW;
AdcaRegs.ADCPPB1CONFIG.bit.CONFIG = 1; //PPB1 is associated with SOC1
AdcaRegs.ADCPPB1OFFCAL.all = aOffset; //PPB1 will subtract OFFCAL value
//to associated SOC
AdcbRegs.ADCPPB1CONFIG.bit.CONFIG = 1; //PPB1 is associated with SOC1
AdcbRegs.ADCPPB1OFFCAL.all = bOffset; //PPB1 will subtract OFFCAL value
EDIS; //to associated SOC
}
//
// End of file
//
