Main system and bus clocks in HCS12 and PLL

Hello guys

i have a question

if the main system clock for the hcs12 mcu is 16 mhz and the bust clock is 500 khz i guess that means there is a prescaler of 20 from system to bus clock??is that right?
my question in another way is if i use the PLL to derive the system and i doubled the main system clock will that double the bus clock??

does anybody know the limits to which i can increase the main clock in the hcs12?

thanks in advance

Re: hcs12 and PLL

Green Soldier said:

if the main system clock for the hcs12 mcu is 16 mhz and the bust clock is 500 khz i guess that means there is a prescaler of 20 from system to bus clock??is that right?
my question in another way is if i use the PLL to derive the system and i doubled the main system clock will that double the bus clock??

Click to expand...

IMHO the bus clock is always half of the core clock. The core clock is either the quartz oscillator, or the PLL.
You might want to check **broken link removed** doc, chapter 9.4.2

does anybody know the limits to which i can increase the main clock in the hcs12?

Click to expand...

This depends on the type of device you're trying to use. The max bus clock of the C32 is 25MHz, some newer devices can go higher.

Re: hcs12 and PLL

z01z said:

Green Soldier said:

if the main system clock for the hcs12 mcu is 16 mhz and the bust clock is 500 khz i guess that means there is a prescaler of 20 from system to bus clock??is that right?
my question in another way is if i use the PLL to derive the system and i doubled the main system clock will that double the bus clock??

Click to expand...

IMHO the bus clock is always half of the core clock. The core clock is either the quartz oscillator, or the PLL.
You might want to check **broken link removed** doc, chapter 9.4.2

does anybody know the limits to which i can increase the main clock in the hcs12?

Click to expand...

This depends on the type of device you're trying to use. The max bus clock of the C32 is 25MHz, some newer devices can go higher.

Click to expand...

thank u very much
but where is the doc?
thanx again