EPROM IDs list

[Barrykearley]

Ive got a checksum of 012c - wtf is that ??

is there anyone whom has a definitive list of these checksums and what the chips are. We should surely be able to pull together a library of images for everyone.

It says s300 on my ecu

[fjmuurling]

Hi Barry,

what is the ID number of your chip?

[Barrykearley]

34 minutes ago, fjmuurling said:

Hi Barry,

what is the ID number of your chip?

[fjmuurling]

Hi Barry,

I think your EPROM ID is 012C. (and not your checksum).

The only S300 BIN file i have has an EPROM ID of 012C, however the PROGRAM ID (engineering byte) is set to $AA, so the ECU skips the checksum routine. Setting the PROGRAM ID to $AA is usually during development / tuning etc of the code. When the code is finalised a checksum will be alculated and stored into the EPROM as well as the proper PROGRAM ID.

The checksum check is for an integrety check of the EPROM.

As far as I know the SE, GT3, S4, S4s and the S300 use the same ECU, it is the contents of the EPROM what makes the difference and maybe the two NETRES chips. I believe the knock circuitry chip is the same in all. In your picture the EPROM is on the right. The white board is the knock (ESC) chip. below the white chip are the 2 NETRES chips.

 

[Barrykearley]

I’m simple @fjmuurling - what does this mean ? What is the chip? And what performance setting are there ?

[fjmuurling]

I'm simple too.

The NETRES chips are just for the limp home mode (emergency running if something goes wrong with the program in the ECU) and the white chips is for the knock detection of the engine.

The EPROM contains the code / parameters for the fuel injection  / ignition / boost etc control.

It looks like the BIN (EPROM code) file I have is the same (012C) as yours (judging by the ID numbers), I don't know if it is an original Lotus one or a modified one. The only information I have about my file is that it is a modified code but that is not confirmed.

Did some digging in the parts lists and found that the PROM ID for the Sport 300 is 300. $012C (hexadecimal) is 300 (decimal) suggesting that the code you have is a stock S300 file.

 

Hope this helps a bit,

Freek

 

[Barrykearley]

So is stock s300 the same as stock S4s ??

[fjmuurling]

according to the partslist not.

[fjmuurling]

Barry,

Judging by the picture of your MEMCAL, it looks like to be Original. No resoldering of the EPROM chip. My bet is that it is an original chip/code.

[tomcattom]

Mine shows an EEPROM ID of 6CE5 too. Although mine appears to have been in an original ECM (there are lotus part numbers etc on the case) it does appear to have been opened at some point prior to me poking about inside it last night.

[sailorbob]

Thanks to Tom I've been able to compare the 0x6CE5 calibration to the 0x1496 'BNUB' calibration and it is very similar with only the following items adjusted:

• PROM ID
• PROM checksum
• VE Low RPM table  (values decreased slightly in the rpm range up to 2400 rpm between the MAP range of 0.3 to 1.12 bar)
• VE Idle RPM table ( mix of increased and decreased values in every cell)
• Idle RPM vs ECT A/C Off function (target idle RPM increased by 25 rpm in the 80 - 103 deg C range)

It appears that the 0x6CE5 calibration is a preproduction version used before GM produced the 0x1496 used on the majority of S4S cars.

[chandrab]

On 14/02/2019 at 10:31, sailorbob said:

VE Idle RPM table ( mix of increased and decreased values in every cell)

Isn't that interesting....I have a 0x6cE5 on my SE, but I was told it was an S4S chip.  Is there any benefit to upgrade to a real S4S chip...or a Powerchip S4S?

 

[sailorbob]

The 0x6CE5 calibration is from a S4S chip. There probably is a little benefit changing to a later S4S calibration but it is more significant to note that no S4S calibration is particularly suited to the SE, or S4, due to the VE tables being incorrect due to the different sized inlet valves and turbocharger.

[MarkL]

Short question: What does VE stand for ?

Do you happen to know the absolute hexadecimal position of this table in SE and or S4S PROM ? What absolute address is the whole PROM mapped to at all ?

[Bibs]

Volumetric Efficiency. 

It's a ratio (or percentage) of the mass of air and fuel that is trapped by the cylinder during induction divided by the mass that would occupy the displaced volume if the air density in the cylinder were equal to the ambient air density*.

*Thanks wikipedia

[Barrykearley]

It’s victory in Europe is it not?