Hi,
The external frequency clock (8MHz for example) is four times the internal
clock (2MHz). So, your instructions are executed with internal clock, 2MHz
(500ns / cycle).

Regards,

Yvan
http://www.ybdesign.fr




"Jeff Fox" <fox@ultratechnology.com> a &#4294967295;crit dans le message de news:
4fbeeb5a.0404051203.5a5910b3@posting.google.com...
> In some literature about the 68HC11 I see a reference to an 8Mhz
> crystal and a 2MHz eClock.  Instructions execute in a given number
> of clock cycles, but which clock?
>
> Best Wishes,
> Jeff Fox

In article <4fbeeb5a.0404051203.5a5910b3@posting.google.com>, 
fox@ultratechnology.com says...
> In some literature about the 68HC11 I see a reference to an 8Mhz
> crystal and a 2MHz eClock.  Instructions execute in a given number
> of clock cycles, but which clock?
> 
> Best Wishes,
> Jeff Fox
> 
Either, it just takes 4 more OSC clock ticks more than E clock ticks ;)

But seriously.....
Most of the documentation refers to E clock cycles.  

In some literature about the 68HC11 I see a reference to an 8Mhz
crystal and a 2MHz eClock.  Instructions execute in a given number
of clock cycles, but which clock?

Best Wishes,
Jeff Fox