Posted on May 17, 2011 at 11:32 Based on the datasheet, it looks like the DIV2 (see MODER register) is required when using a crystal :
''Since the input clock to the Clock Multiplier circuit requires a 50% duty cycle for correct PLL operation, the divide by two circuit should be
enabled when a crystal oscillator is used''
However, how can we reach the ST9 maximum clock speed (24MHz) with a standard crystal ?
The easiest solution would have been to clock the micro with a 4Mhz crystal and remove the DIV2 option.
Does anyone have tried to remove the DIV2 bit ?
Did it work with your design ?
Jojo
