STM8S208 external clock

[ptsmith]

Posted on June 24, 2009 at 08:15

STM8S208 external clock

[ptsmith]

Posted on May 17, 2011 at 15:03

I would like to run an STM8S208RBT6 from an external 1 Mhz clock. However, it appears that if I do this the ADC cannot be used since the ADC requires at least a 1 MHz clock, and the minimum ADC clock prescale ratio is /2 from fMASTER.

So, am I correct that in order to use the ADC, the minimum external clock is 2 MHz? Paul Smith Indiana University Physics

[mozra27]

Posted on May 17, 2011 at 15:03

Hi Paul,

Yes, you are right the minimum value for fADC is 1MHz can by a prescaled fMASTER clock. The prescaling factor of the clock depends on the SPSEL[2:0] bits in the ADC_CR1 register. Regards mozra