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Functions | Variables
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 "pic24_unittest.h"
#include <stdio.h>

Go to the source code of this file.

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 configBasic (const char *sz_helloMsg)
 
uint32_t roundFloatToUint32 (float f_x)
 
uint16_t roundFloatToUint16 (float f_x)
 
uint16_t compute_brg (uint32_t u32_fcy, uint16_t u16_brgh, uint32_t u32_baudrate)
 

Variables

static _PERSISTENT const char * sz_lastError
 
_PERSISTENT const char * sz_lastTimeoutError
 
static uint16_t u16_INTTREGlast
 

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.

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 153 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 199 of file pic24_util.c.

Referenced by printResetCause().

void checkOscOption ( void  )

Reports the oscillator currently in use to the default serial port. See FNOSC_SEL for a table of which chips support which clocks.

Definition at line 271 of file pic24_util.c.

Referenced by printResetCause().

uint16_t compute_brg ( uint32_t  u32_fcy,
uint16_t  u16_brgh,
uint32_t  u32_baudrate 
)

Choose UART baud rate, based on u32_fct. NOTE: Be careful about using BRGH=1 - this uses only four clock periods to sample each bit and can be very intolerant of baud rate % error - you may see framing errors. BRGH is selected via the DEFAULT_BRGH1 define above.

Definition at line 465 of file pic24_util.c.

Referenced by configUART1().

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 425 of file pic24_util.c.

void configHeartbeat ( void  )

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

See Also
doHeartbeat

Definition at line 82 of file pic24_util.c.

Referenced by configBasic().

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 98 of file pic24_util.c.

Referenced by configHeartbeat(), doErasePageFlash(), doWriteRowFlash(), inChar1(), ioMasterSPI1(), 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 320 of file pic24_util.c.

Referenced by configBasic().

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 187 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 174 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 451 of file pic24_util.c.

Referenced by compute_brg(), 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 439 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 110 of file pic24_util.c.

Referenced by doHeartbeat().

Variable Documentation

_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 120 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 125 of file pic24_util.c.

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

uint16_t u16_INTTREGlast
static

Store a copy of the INTTREG register as a bitfield. This is not defined for all PICs, so work around with an #ifdef of ILR, one of the bitfields in this register. 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 145 of file pic24_util.c.

Referenced by _DefaultInterrupt(), and printResetCause().

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 71 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 75 of file pic24_util.c.

Referenced by configHeartbeat(), and doHeartbeat().