Watchdog in CodevisionAVR

[ns2014]

Dear All,
I'm looking for an example for using the Watchdog timer in Codevision but I cannot find any.
I used the Wizard to generate the code to include the Watchdog timer

// Crystal Oscillator division factor: 1
#pragma optsize-
CLKPR=0x80;
CLKPR=0x00;
#ifdef _OPTIMIZE_SIZE_
#pragma optsize+
#endif

but I was expecting some straightforward functions such as:
watchdog_enable() //to reset and start the timer
watchdog_disable()// to stop the timer

I couldn't find any example.
I'm also puzzled with the code above:
CLKPR=0x80;
CLKPR=0x00;
how come it is overwriting the same flag? it is new to me
Thanks

 

[alexan_e]

How about cheching the AVR datasheet for the purpose of the consequent writes to the CLKPR register?

 

[ns2014]

Thanks for the pointer. I just checked the datasheet and realized that they are using the sequence purposefully.

To elaborate more on my example request:
I'm using USART to communicate between two MCUs. I'm using getchar() to receive the data. sometimes one unit hangs, so the other keeps waiting indefinitely for the data.
I want to use the watchdog timer to ensure if the communication is not received within x ms, I reset the units. and start over.
I'm expecting the code flow as:
//start the timer
enable_wdt();
get_char()
disable_wdt()

so if disable_wdt is reached this means getchar() received the byte and then the watchdog timer is disabled and the code continue the execution normally. but if get_char() hangs then I restart the unit.
thanks