CCS C Compiler Manual PCB / PCM / PCH

Functional Overview
WDT or Watch Dog Timer
Different chips provide different options to enable/disable or configure the WDT.
Relevant Functions:
setup_wdt()
restart_wdt()
Enables/disables the wdt or sets the prescalar.
Restarts the wdt, if wdt is enables this must be periodically called
to prevent a timeout reset.
For PCB/PCM chips it is enabled/disabled using WDT or NOWDT fuses whereas on PCH
device it is done using the setup_wdt function.
The timeout time for PCB/PCM chips are set using the setup_wdt function and on PCH using
fuses like WDT16, WDT256 etc.
RESTART_WDT when specified in #USE DELAY, #USE I2C and #USE RS232 statements like
this #USE DELAY(clock=20000000, restart_wdt) will cause the wdt to restart if it times out
during the delay or I2C_READ or GETC.
Relevant Preprocessor:
#FUSES WDT/NOWDT
#FUSES WDT16
Enabled/Disables wdt in PCB/PCM devices
Sets ups the timeout time in PCH devices
Relevant Interrupts:
None
Relevant Include Files:
None, all functions built-in
Relevant getenv() parameters:
None
Example Code:
For PIC16F877
#fuses wdt
setup_wdt(WDT_2304MS);
while(true){
restart_wdt();
perform_activity();
}
For PIC18F452
#fuse WDT1
setup_wdt(WDT_ON);
while(true){
restart_wdt();
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