differences between spi on mc9s256a and mc9s256cfu ?

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differences between spi on mc9s256a and mc9s256cfu ?

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joegibson
Contributor I
the problem began when the mc9s256a (bat wing logo) was discontuined and i started using the mc9s256cfu part (new freescale logo). i have cpu's running on a single spi bus. all cpu are slaves except when changed to master to speek to other cpu's. this is a polled system with each cpu addressed. the only way i can get the mc9s256cfu to receive data is to invert both cpol and cpha when setting up slave. in testing i install 256a and it works, same board with 256cfu and will not work. then i clear cpol, and cpha bits and the 256cfu then works. no other changes are made to the other cpu's on the buss.
thanks
joe
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Lundin
Senior Contributor IV
I would suspect that the early chips in the A family had silicon bugs that the C family is missing. I think there was an errata related to the SPI flags in the early masks, I would take a closer look at those.
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joegibson
Contributor I
Thanks Lundin, I will do that.
joe
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Alban
Senior Contributor II
Hello,

Difficult to comment as these references do not exist.

CFU means Commercial temperature and FU stands for the package (80QFP).
256 probably means 256KB of flash memory.
MC9S is not enough to determine a family.

As no S08 has a that big flash yet, we can only think about 1 large family of products: S12.
Still letters are missing:
MC9S12??256CFU

Regards,
Alban.
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Lundin
Senior Contributor IV
I assumed he ment porting from S12A to S12C since those are similar. Regardless, the advise is still to check the erratas for the earlier masks since that's the only difference.
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joegibson
Contributor I
part # MC9S12A256BCFU (OLD PART) AND MC9S12A256CFUE (NEW PART)
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Alban
Senior Contributor II
Hello Joe,

The difference, the "E", here means that the new part is lead free / RoHS compliant.

For you to read the Mask Set Errata sheet (MSE), you can look into keyword search for the mask set.
Mask is written underneath the part number and is formatted:

0X00X
with 0 a digit between 0 and 9.
with X a letter between A and Z

EDIT: I was pinpointed to the "B" in the part you had before and I just didn't see.
This means this part has older flash generation (see datasheet for actual numbers) and probably other module enhancements.
There are quite a few posts on here about the SPI and they could be of great help to you ?

Alban.


Message Edited by Alban on 2007-09-28 11:47 AM
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