spuggy |
10-09-2023 12:24 PM |
Quote:
Originally Posted by bickyd
(Post 12105631)
I did not know that. Thank you.
|
Cough. Probably because it's not correct.
From iscmhitz's post Permalink in this thread DME Update Questions:
Quote:
There are different two 24-pin EPROMs out there and not all are 2k. The very first rendition of the 3.2 Motronic used a 2716 with 2kx8 capacity. The base code is located in the CPU and the EPROM contains personalization (maps, calibration, high-level routines)
At some point with the EPROM development moving forward the 27C32 with 4kx8 space and still 24 pins was used by Bosch. The code initially didn't make use of the addition space and two identical 2k-sized copies resided in the 4k EPROM. The base code was still in the CPU. Later versions used the full 4k of the EPROM.
Then once again the the 27C32 EPROM was replaced by the 27C64 EPROM with 8kx8 space and 28 pins. Now the entire code now resides in the EPROM and the internal code of the CPU is disabled.
The jumpers account for the different 24-pin versions of the EPROM. Pin 21 needs to be Vcc for the 2716 to function properly and A11 for the 27C32 IF it is a real 4k later version. The other important thing to keep in mind is that most modern chips now come in a much larger EPROM (27C512) and there should be 8 identical copies inside so the jumpering doesn't matter. The 27C512 is the only EPROM currently still in production. If the chip is in any other EPROM it is a "pull" that has been erased. In other words its an old device that has been sourced somewhere on the used market.
|
(you can largely ignore Loren/Dave, as usual. Yes, he's technically correct - but contributing little, as he often does).
This is not processing speed, it's setting the capacity of the chip that stores the maps and the Motronic firmware.
Ditch the bloody Motronics already. It's freaking 80's tech - 40 years old. Less processing than your microwave or your toaster, much less your phone. It can't deal with anything "fancy" - much less anything that didn't exist in the 80's. It's like trying to hang on to CIS - why would you do that?
And you need a piggy-back emulator to read/program a Motronic in real time (yes, they exist - a guy here builds them) - which almost any ECU built in the last 20 years or so just gives you out of the box. But this still doesn't let you drive boost control, variable cam timing, exhaust valves etc - or even datalogging.
|