Hello:
I'm relatively new to this product (TM4C1294 board) and I am wondering what is the correct way of enabling the ADC0 module to take analog inputs from multiple different ports. Specifically, I am looking to use pins PE0, PE1, PE2, PE3, PD7, PK0, and PK1. I generated some code using the PinMux utility, then I configurined each step of ADC sequencer 0. Next, inside a loop, I clear the ADC status flag, trigger a conversion. Then I wait for the conversion process to complete (checking the flag) but it never finishes. I am missing something here, but I am not sure what.
I've attached my code to this post. I'm pretty new to this, so help would be appreciated :)
Thanks
Tom
//*****************************************************************************
//
// timers.c - Timers example.
//
// Copyright (c) 2013-2014 Texas Instruments Incorporated. All rights reserved.
// Software License Agreement
//
// Texas Instruments (TI) is supplying this software for use solely and
// exclusively on TI's microcontroller products. The software is owned by
// TI and/or its suppliers, and is protected under applicable copyright
// laws. You may not combine this software with "viral" open-source
// software in order to form a larger program.
//
// THIS SOFTWARE IS PROVIDED "AS IS" AND WITH ALL FAULTS.
// NO WARRANTIES, WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT
// NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. TI SHALL NOT, UNDER ANY
// CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
// DAMAGES, FOR ANY REASON WHATSOEVER.
//
// This is part of revision 2.1.0.12573 of the EK-TM4C1294XL Firmware Package.
//
//*****************************************************************************
#include <stdint.h>
#include <stdbool.h>
#include "adc_pinmux.h"
#include "inc/hw_gpio.h"
#include "inc/hw_ints.h"
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "driverlib/adc.h"
#include "driverlib/debug.h"
#include "driverlib/fpu.h"
#include "driverlib/gpio.h"
#include "driverlib/interrupt.h"
#include "driverlib/pin_map.h"
#include "driverlib/rom.h"
#include "driverlib/rom_map.h"
#include "driverlib/sysctl.h"
#include "driverlib/timer.h"
#include "driverlib/uart.h"
#include "utils/uartstdio.h"
//****************************************************************************
//
// System clock rate in Hz.
//
//****************************************************************************
uint32_t g_ui32SysClock;
//*****************************************************************************
//
// Flags that contain the current value of the interrupt indicator as displayed
// on the UART.
//
//*****************************************************************************
uint32_t g_ui32Flags;
//*****************************************************************************
//
// The error routine that is called if the driver library encounters an error.
//
//*****************************************************************************
#ifdef DEBUG
void
__error__(char *pcFilename, uint32_t ui32Line)
{
}
#endif
//*****************************************************************************
//
// Configure the ADC Ports and Pins
//
//*****************************************************************************
void
ADCPortInit(void)
{
//
// Enable Peripheral Clocks
//
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_ADC0);
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOD);
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE);
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOK);
//
// Enable pin PE3 for ADC AIN0
//
MAP_GPIOPinTypeADC(GPIO_PORTE_BASE, GPIO_PIN_3);
//
// Enable pin PK1 for ADC AIN17
//
MAP_GPIOPinTypeADC(GPIO_PORTK_BASE, GPIO_PIN_1);
//
// Enable pin PE2 for ADC AIN1
//
MAP_GPIOPinTypeADC(GPIO_PORTE_BASE, GPIO_PIN_2);
//
// Enable pin PE1 for ADC AIN2
//
MAP_GPIOPinTypeADC(GPIO_PORTE_BASE, GPIO_PIN_1);
//
// Enable pin PK0 for ADC AIN16
//
MAP_GPIOPinTypeADC(GPIO_PORTK_BASE, GPIO_PIN_0);
//
// Enable pin PD7 for ADC AIN4
// First open the lock and select the bits we want to modify in the GPIO commit register.
//
HWREG(GPIO_PORTD_BASE + GPIO_O_LOCK) = GPIO_LOCK_KEY;
HWREG(GPIO_PORTD_BASE + GPIO_O_CR) = 0x80;
//
// Now modify the configuration of the pins that we unlocked.
//
MAP_GPIOPinTypeADC(GPIO_PORTD_BASE, GPIO_PIN_7);
//
// Enable pin PE0 for ADC AIN3
//
MAP_GPIOPinTypeADC(GPIO_PORTE_BASE, GPIO_PIN_0);
}
//*****************************************************************************
//
// Configure the UART and its pins. This must be called before UARTprintf().
//
//*****************************************************************************
void
ConfigureUART(void)
{
//
// Enable the GPIO Peripheral used by the UART.
//
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);
//
// Enable UART0.
//
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_UART0);
//
// Configure GPIO Pins for UART mode.
//
//ROM_GPIOPinConfigure(GPIO_PA0_U0RX);
//ROM_GPIOPinConfigure(GPIO_PA1_U0TX);
//ROM_GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1);
//
// Initialize the UART for console I/O.
//
UARTStdioConfig(0, 115200, g_ui32SysClock);
}
//*****************************************************************************
//
// This example application demonstrates the use of the timers to generate
// periodic interrupts.
//
//*****************************************************************************
int
main(void)
{
//
// Set the clocking to run directly from the crystal at 120MHz.
//
g_ui32SysClock = MAP_SysCtlClockFreqSet((SYSCTL_XTAL_25MHZ |
SYSCTL_OSC_MAIN |
SYSCTL_USE_PLL |
SYSCTL_CFG_VCO_480), 120000000);
// holds digital values from each of the ADC channels
volatile uint32_t reading0, reading1, reading2, reading3,
reading4, reading5, reading6;
// Create an array that will be used for storing the data read from the ADC FIFO.
// It must be as large as the FIFO for the sequencer in use. We will be using
// sequencer 0 which has a FIFO depth of 8.
uint32_t ui32ACCValues[8];
//
// Initialize the UART and write status.
//
ConfigureUART();
UARTprintf("Thanks Mr. UART\nGood code and many null-terminated\n strings will come to you but only if you\nprint this statement\nin at least three other functions");
// Enable ADC0 and pins
SysCtlPeripheralEnable(SYSCTL_PERIPH_ADC0);
ADCPortInit();
// Enable GPIO E, D, A, K
//SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE);
//SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOD);
//SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA); // no ADC0 ports on GPIO A
//SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOK);
// Configure the seven GPIO pins to be analog inputs
//GPIOPinTypeADC(GPIO_PORTE_BASE, GPIO_PIN_0 | GPIO_PIN_1 | GPIO_PIN_2 | GPIO_PIN_3);
//GPIOPinTypeADC(GPIO_PORTD_BASE, GPIO_PIN_7);
//GPIOPinTypeADC(GPIO_PORTA_BASE, GPIO_PIN_6); // no ADC0 ports on GPIO A
//GPIOPinTypeADC(GPIO_PORTK_BASE, GPIO_PIN_1 | GPIO_PIN_2);
// Configure steps in the ADC sequencer.
ADCSequenceStepConfigure(ADC0_BASE, 0, 0, ADC_CTL_CH0);
ADCSequenceStepConfigure(ADC0_BASE, 0, 1, ADC_CTL_CH1);
ADCSequenceStepConfigure(ADC0_BASE, 0, 2, ADC_CTL_CH2);
ADCSequenceStepConfigure(ADC0_BASE, 0, 3, ADC_CTL_CH3);
ADCSequenceStepConfigure(ADC0_BASE, 0, 4, ADC_CTL_CH4);
ADCSequenceStepConfigure(ADC0_BASE, 0, 5, ADC_CTL_CH5);
ADCSequenceStepConfigure(ADC0_BASE, 0, 6, ADC_CTL_CH6|ADC_CTL_IE|ADC_CTL_END);
//
// Loop forever
//
while(1)
{
// Clear the ADC status flag
ADCIntClear(ADC0_BASE, 0);
// Trigger the ADC conversion with software.
ADCProcessorTrigger(ADC0_BASE, 0);
// Wait for the conversion process to complete
while(!ADCIntStatus(ADC0_BASE, 0, false)) { }
// Read the ADC value from the ADC Sample Sequencer 1 FIFO.
ADCSequenceDataGet(ADC0_BASE, 0, ui32ACCValues);
// Add these final three lines to move the values into some variables with more friendly sounding names
reading0 = ui32ACCValues[0];
reading1 = ui32ACCValues[1];
reading2 = ui32ACCValues[2];
reading3 = ui32ACCValues[3];
reading4 = ui32ACCValues[4];
reading5 = ui32ACCValues[5];
reading6 = ui32ACCValues[6];
// print the values
UARTprintf("AIN0 =\t%4d\t%4d\t%4d\t%4d\t%4d\t%4d\t%4d\t\r",
reading0, reading1, reading2, reading3, reading4, reading5, reading6);
int i = 0;
while (++i < 100000); // pause temporarily
}
}
