68HC908 programming 32.768 kHz crystal

I am trying to learn the HC908.
From what I understand, I require just a MAX232, resistors, jumpers,
and a 32.768 kHz crystal, power and serial data than I should be ready
to go� maybe.
Is it possible to program the chip without a higher (8 MHz?)
oscillator?
IE using the PLL w/o software control.
Anyone have any basic circuits that they could recommend to help me
get started?
Any help is greatly appreciated.

galto wrote:
> I am trying to learn the HC908.
> From what I understand, I require just a MAX232, resistors, jumpers,
> and a 32.768 kHz crystal, power and serial data than I should be ready
> to go� maybe.
> Is it possible to program the chip without a higher (8 MHz?)
> oscillator?
> IE using the PLL w/o software control.
> Anyone have any basic circuits that they could recommend to help me
> get started?
> Any help is greatly appreciated.


You've got the general idea, but the details are different
for the various members of the HC908 family.
Goto www.freescale.com and in about 3 clicks you can be
at the selection page for the 908 family.  Pick the one
you are using and download the User's Manual.  All will
be revealed.

There is a good programmer schematic in the manual. You can also use a 
simple 74hcu04 crystal osc. running at 4.9152mc which works better. To 
communicate and upload your program visit the P&E website for a free 
assembler/programmer, http://www.pemicro.com

SFC

"galto" <digital_gecko@yahoo.com> schreef in bericht 
news:af73de95.0411091943.2e8a97f5@posting.google.com...
>I am trying to learn the HC908.
> From what I understand, I require just a MAX232, resistors, jumpers,
> and a 32.768 kHz crystal, power and serial data than I should be ready
> to go. maybe.
> Is it possible to program the chip without a higher (8 MHz?)
> oscillator?
> IE using the PLL w/o software control.
> Anyone have any basic circuits that they could recommend to help me
> get started?
> Any help is greatly appreciated.