S12 / MagniV MicrocontrollersのトピックHow to enter Stop or Wait Mode?

How to enter Stop or Wait Mode?

aguo1223 — Fri, 23 Nov 2012 02:54:09 GMT

Hello all,

how to enter Stop or Wait mode when mcu is running?

PS: MC9S12P128.

Re: How to enter Stop or Wait Mode?

TomE — Tue, 27 Nov 2012 00:08:56 GMT

The purpose of this forum is to ask questions about how to use the forums, not how to use the products.

Please ask your question in the appropriate 8 or 16 bit forum, but SEARCH those forums first to see if someone else has already asked your question.

8-bit Microcontrollers

16-Bit Microcontrollers

These forums can be accessed directly under the "Products" section of the "Home" page.

Can one of the Administrators move this post please?

Tom

Re: How to enter Stop or Wait Mode?

aguo1223 — Tue, 27 Nov 2012 09:01:18 GMT

Thanks

Re: How to enter Stop or Wait Mode?

RadekS — Tue, 27 Nov 2012 09:53:42 GMT

For entrance into STOP and WAIT mode you should use directly CPU instructions.

You can use for example:

asm STOP; //STOP mode

asm WAI; //force the MCU into wait mode

In case of STOP mode, there is necessary also clear S bit in CCR register prior you use STOP instruction, otherwise STOP instruction will be executed as NOP.

So, you can use this code:

asm ANDCC #0x7F; //clear S bit - enable the stop mode. If the S bit is not

//cleared then STOP instruction has no effect and is

//executed as a dummy instruction NOP.

asm STOP; //STOP mode

Note: S bit will be restored during next reset.