Differences between MC9S12 CPUs

[sub]

Hello,

i got some MC9S12C64MFAE µCs... my ms2-board hat C64CFAE on it.
What are the differences and will the MFAE work also?

Greetings, Stephan

[sub]

ok, i think i found the differences ...

CFAEs maximum operation temperature is 85°C
MFAEs is 125°C

feel free to correct me if i'm wrong.

i wonder why original bg-boards use the 85°C version...

[acab]

Is it real to use MC9S12XS128 instead MC9S12C64?

[SymTech Laboratories]

ok, i think i found the differences ...

CFAEs maximum operation temperature is 85°C
MFAEs is 125°C

feel free to correct me if i'm wrong.

i wonder why original bg-boards use the 85°C version...

This is an old post, but that's correct, "C" signifies -40°C to 85°C operation and "M" signifies -40°C to 125°C operation. Keep in mind that most MegaSquirt products aren't designed for under hood installation, so the increased operating temperature range isn't necessary.

[SymTech Laboratories]

Is it real to use MC9S12XS128 instead MC9S12C64?

That won't work. The S12XS is a completely different device than the S12C.

[acab]

What about MC9S12C96 and MC9S12C12 instead of MC9S12C64 for future programming?

[SymTech Laboratories]

What about MC9S12C96 and MC9S12C12 instead of MC9S12C64 for future programming?

Assuming you mean MC9S12C128, in our experience there's no problem substituting a chip with more Flash for one with less, but there's no advantage -- they cost more and the code isn't written to take advantage of the extra memory. Considering how many MS2 systems are out there using the C64 chip, it's unlikely the code will ever be rewritten to support the C96 or C128 chips.

[racingmini_mtl]

What about MC9S12C96 and MC9S12C12 instead of MC9S12C64 for future programming?

Assuming you mean MC9S12C128, in our experience there's no problem substituting a chip with more Flash for one with less, but there's no advantage -- they cost more and the code isn't written to take advantage of the extra memory. Considering how many MS2 systems are out there using the C64 chip, it's unlikely the code will ever be rewritten to support the C96 or C128 chips.

While it's true that it costs more, it's not true that the code doesn't use the memory. The C64 is actually a C128 with a different label. The MS2/Extra takes advantage of this and uses the additional flash space.

Jean

[SymTech Laboratories]

While it's true that it costs more, it's not true that the code doesn't use the memory. The C64 is actually a C128 with a different label. The MS2/Extra takes advantage of this and uses the additional flash space.

That's right, we forgot about the additional 64k in the C64. In general, the dies are the same from one chip to another in the same family, but the higher memory addresses are permanently inaccessible. For instance, 32k is the limit in the very first MS2 cards with C32 chips.

[racingmini_mtl]

The C32 is probably a different die because it also has 2K RAM instead of 4K.

Jean

[SymTech Laboratories]

The C32 is probably a different die because it also has 2K RAM instead of 4K.

That's possible -- but we're digressing.

acab, to answer your question, you can use the MC9S12C128, but there's no benefit as it has the same amount of accessible memory as the C64 and it costs significantly more in single unit quantities.

[jsmcortina]

The C32 IS a different die, do not try to use it for Megasquirt.

C64, 96, 128 are the same die and work interchangeably.

See page 679 of the MC9S12C128 datasheet v 01.20

James

[SymTech Laboratories]

The C32 IS a different die, do not try to use it for Megasquirt.

C64, 96, 128 are the same die and work interchangeably.

We edited that last post. "C32" was a typo, we meant that the C128 has the same amount of accessible memory as the C64.