I have a working watchdog on the ATTiny, period set to 8sec, no issues.
However, I need to switch to the external oscillator.
My sequence after power on is :
Disable the watchdog
Attempt to do the clock switch : currently limited to the following lines of code
/* Save the current system clock source */
CLKCSR = 1 << CLKCCE;
CLKCSR = CLOCK_RECOVER;
Reset the watchdof (WDR instruction), then enable the watchdog as per datasheet
This results in the watchdog resetting immediately.
If I just remove the line CLKCSR = CLOCK_RECOVER, the watchdog works fine.
Hence somehow writing a command to CLKCSR is having an effect on the watchdog.
Please could someone advise
As soon as I write a command to CLKCSR