i've looked up f877 datasheet and TMR1 has its own control register (we can enable and disable it) and it's two paired (TMR1H and TRM1L)

i am not sure but this is algorythm as i understand, if TMR1L=255 then TRM1H=TMR1H+1

and if i sum them up, timepassed=TRM1H*255+TMR1L i can find time in useconds.

Thanks for your helps.

Quote Originally Posted by grimmjow View Post
Yes i do not have obligation to use f84, and i know f877 has Timer1(16bit). Let us check this;

i will use 4MHZ xtal and f877, and it has 16 bit timer ~= 66ms is more than enough for me.

So i do not need to use watchdog timer prescaler commands and i just need to use,

OPTION_REG.5=1 and OPTION_REG.5=0 commands for timer right?