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pic24_util.c File Reference
#include "pic24_util.h"
#include "pic24_serial.h"
#include "pic24_clockfreq.h"
#include "pic24_ports.h"
#include "pic24_delay.h"
#include <stdio.h>

Go to the source code of this file.

Macros

#define u16_INTTREGlast   BITS2WORD(INTTREGBITS_last)
 

Functions

void _ISR _DefaultInterrupt (void)
 
void reportError (const char *sz_errorMessage)
 
uint32_t readProgramMemory (uint32_t u32_address)
 
void checkDeviceAndRevision (void)
 
void checkOscOption (void)
 
void printResetCause (void)
 
void configPinsForLowPower (void)
 
void configBasic (const char *sz_helloMsg)
 
uint32_t roundFloatToUint32 (float f_x)
 
uint16_t roundFloatToUint16 (float f_x)
 

Variables

static _PERSISTENT const char * sz_lastError
 
_PERSISTENT const char * sz_lastTimeoutError
 
static _PERSISTENT INTTREGBITS INTTREGBITS_last
 

Heartbeat

These routines provide heartbeat support by blinking a LED on a regular basis. See doHeartbeat() for more information.

uint32_t u32_heartbeatCount
 
static uint32_t u32_heartbeatMax
 
void configHeartbeat (void)
 
void doHeartbeat (void)
 
void toggleHeartbeat (void)
 

Detailed Description

This file contains implmentations for functions prototyped in pic24_util.h.

Definition in file pic24_util.c.

Macro Definition Documentation

#define u16_INTTREGlast   BITS2WORD(INTTREGBITS_last)

Make the INTTREGBITS_last also accessible as a word. This is like uint16_t u16_INTTREGlast except that INTTREGBITS_last and u16_INTTREGlast refer to the same data.

Definition at line 139 of file pic24_util.c.

Referenced by _DefaultInterrupt(), and printResetCause().

Function Documentation

void _ISR _DefaultInterrupt ( void  )

Provide a default interrupt handler which records what interrupt was not handled then resets the chip. Typically, a call to printResetCause during chip startup will then print the error.

Definition at line 149 of file pic24_util.c.

void checkDeviceAndRevision ( void  )

Determines the device and revision of the PIC this program is executing on. This information is then output via the default UART. A warning message is issued if this program was not compiled for the chip it is running on.

Definition at line 195 of file pic24_util.c.

Referenced by printResetCause().

void checkOscOption ( void  )

Reports the oscillator currently in use to the default serial port.

Definition at line 266 of file pic24_util.c.

Referenced by printResetCause().

void configBasic ( const char *  sz_helloMsg)

Perform basic chip configuration:

  • Configure the heartbeat
  • Configure the clock
  • Configure UART1
  • Determine and print the cause of reset
  • Print a hello message.
Parameters
sz_helloMsgHello message to print.

Definition at line 501 of file pic24_util.c.

Referenced by main().

void configHeartbeat ( void  )

Configures a GPIO pin for use with the heartbeat and sets up the heartbeat counter.

See Also
doHeartbeat

Definition at line 81 of file pic24_util.c.

Referenced by configBasic(), and main().

void configPinsForLowPower ( void  )

This function puts the PIC24 in low-power mode by:

  • Configuring all digital I/O pins as inputs
  • Configuring all analog I/O pins shared with digital I/O pins to be digital only
  • Enables pullups on all pins not used by the oscillator.

WARNING: if pullups are enabled on pins used by the oscillator, the clock typically stops running. Currently, this code works for demo purposes with the FRC oscillator when used in the reset.c program. It should also work with primary and secondary oscillators, using conditional compiles in the code.

Definition at line 487 of file pic24_util.c.

Referenced by main().

void doHeartbeat ( void  )

This heartbeat function should be called repeatedly in any sort of blocking wait loop. It will periodically toggle an LED after u32_heartbeatMax increments.

Definition at line 97 of file pic24_util.c.

Referenced by configHeartbeat(), doErasePageFlash(), doWriteRowFlash(), inChar1(), ioMasterSPI1(), main(), outChar1(), WAIT_UNTIL_CONVERSION_COMPLETE_ADC1(), and WAIT_UNTIL_TRANSMIT_COMPLETE_UART1().

void printResetCause ( void  )

Determines and prints the cause of a CPU reset. This should be called when the chip first starts up. For an example, see the configBasic function.

Definition at line 313 of file pic24_util.c.

Referenced by configBasic(), and main().

uint32_t readProgramMemory ( uint32_t  u32_address)

Reads a 24-bit program memory word at the given address.

Parameters
u32_addressAddress of program memory to read.
Returns
The 24-bit program memory word at u32_address. The upper 8 bits are 0.

Definition at line 183 of file pic24_util.c.

Referenced by checkDeviceAndRevision().

void reportError ( const char *  sz_errorMessage)

Report a critical error by recording a message in sz_lastError then resetting the chip, assuming hat printResetCause will be called during chip initialization.

Parameters
sz_errorMessageError message to report.
See Also
REPORT_ERROR

Definition at line 170 of file pic24_util.c.

Referenced by _DefaultInterrupt(), checkOscOption(), checkRxErrorUART1(), picAssert(), and putI2C1().

uint16_t roundFloatToUint16 ( float  f_x)

Round a floating-point number to the nearest integer.

Parameters
f_xFloating-point value to round
Returns
The nearest uint16_t to f_x.

Definition at line 526 of file pic24_util.c.

Referenced by configUART1(), msToU16Ticks(), and usToU16Ticks().

uint32_t roundFloatToUint32 ( float  f_x)

Round a floating-point number to the nearest integer.

Parameters
f_xFloating-point value to round
Returns
The nearest uint32_t to f_x.

Definition at line 514 of file pic24_util.c.

Referenced by ticksToMs(), ticksToNs(), ticksToUs(), and usToU32Ticks().

void toggleHeartbeat ( void  )

A function which toggles the hearbeat LED.

See Also
doHeartbeat

Definition at line 109 of file pic24_util.c.

Referenced by doHeartbeat().

Variable Documentation

_PERSISTENT INTTREGBITS INTTREGBITS_last
static

Store a copy of the INTTREG register as a bitfield. This is not defined for the PIC24F, so work around with an #ifdef. This is _PERSISTENT so that it survives the resets which occurs immeidately after the default interrupt handler _DefaultInterrupt copies INTTREG to this variable.

Definition at line 133 of file pic24_util.c.

Referenced by printResetCause().

_PERSISTENT const char* sz_lastError
static

Persistent storage for an error message, typically set by reportError and reported at reset by printResetCause.

Definition at line 119 of file pic24_util.c.

Referenced by printResetCause(), and reportError().

_PERSISTENT const char* sz_lastTimeoutError

Persistent storage for a timeout error, to be reported if a watchdog reset occurs.

Definition at line 123 of file pic24_util.c.

Referenced by convertADC1(), getI2C1(), printResetCause(), putI2C1(), putNoAckCheckI2C1(), rstartI2C1(), startI2C1(), and stopI2C1().

uint32_t u32_heartbeatCount

The current heartbeat count. When this value reaches u32_heartbeatMax, the heatbeat LED is toggled by doHeartbeat().

See Also
doHeartbeat

Definition at line 70 of file pic24_util.c.

Referenced by configHeartbeat(), delayAndUpdateHeartbeatCount(), and doHeartbeat().

uint32_t u32_heartbeatMax
static

When u32_heartbeatCount reaches this maximum, the heatbeat LED is toggled by doHeartbeat().

Definition at line 74 of file pic24_util.c.

Referenced by configHeartbeat(), and doHeartbeat().