topic Re: MC9S08 non volatile trim register in 8-bit Microcontrollers

MC9S08 non volatile trim register

Neil — Tue, 29 Aug 2006 21:27:27 GMT

Hi all.

I am using codewarrior V3.1 with a Softec programmer. In the processor expert bean for a MC9S08QG8CPB I have enabled "initialize trim value" and the default non volatile trim value locations are FFAF and FFAE. These values are loaded into the trim locations 3A and 3B when my program starts. My problem is that the trim values are actually being programmed into FFBE and FFBF instead of FFAF and FFAE. FFAF and FFAE remain blank, so when my program starts, it loads FF into the trim value and my bus freq is way out. Now if I go into the processor expert cpu bean, and change the trim value save locations to FFBE and FFBF, everything works fine. Looks like an error in the bean or something. Is anyone else having this problem with the QG8 ??.

Neil.

Re: MC9S08 non volatile trim register

RockyRoad — Wed, 30 Aug 2006 03:30:04 GMT

Neil -

The Processor Expert bean is correct. The flash locations for the trim are $FFAE and $FFAF. $FFBE and $FFBF are wrong. (In fact, $FFBF is the NVOPT register.)

The issue is with the SofTec programmer. There is a fix so that it puts the trim value in the right location. The fix is in the attached zip file. Upzip it and place the "SofTec_BDC08.DLL" in the following CodeWarrior directory (replacing the existing file):

C:\Program Files\Metrowerks\CW08 V3.1\prog (assumes that you installed to the default locations)

BTW - This is fixed in CodeWarrior08 5.x

- Rocky

Message Edited by RockyRoad on 2006-08-29 03:31 PM

Re: MC9S08 non volatile trim register

Neil — Wed, 30 Aug 2006 19:33:39 GMT

Awesome. downloaded new file and all is working fine now. Thanks so much for your help.

Neil.