original bsi and ecu files

[ozvtr]

For most of the ECUs, EEPROMS store non volatile memory.
Some ECU's use 3 types of memory. Flash, EEPROM and RAM.
The flash memory contains the firmware (the operating system). It contains a set of instructions of how the CPU is to go about it's business. This does not change, power on or power off. But can be re-written by an external device. While it can be re-written it's not really designed to do so. They are designed not to be written to, but read from very quickly.

The RAM contains temporary data that needs to be manipulated quickly but can be "forgotten" if power is removed. These are typically, results of mathematical calculations made by the CPU. But are only important right there and then. RAM is designed to be written to and read from very quickly.

EEPROMS are used to store data that can be temporarily or permanently changed, but need to be "remembered" if the power goes off. Some data is constantly changed, and some data never changes. Like the engine ECU PIN code, which never changes, or previous fuel trim calculations, which constantly changes. Reading from and writing to the EEPROM is very slow by comparison. The data is typically only used for reference by the CPU and is not required to be manipulated quickly. Usually if this data was to be changed, it would be done just as the car is shut down.

All of these systems are VERY reliable! You would have to be very unlucky to corrupt these memories.

[Rhothgar]

For most of the ECUs, EEPROMS store non volatile memory.

Thanks for detailed explanation.

Today I got the problem solved.

Watch the Diagnostics section for a post over the weekend for more information if you’re interested.

Tonight I was filming a video of taking out the EEPROM and programming it.

I didn’t get that far. I ended up pulling up two copper pads on the eeprim because the chip was glued down with far more glue than I have ever seen on one of these ECU’s.

I should have just cloned the old ECU with the virginised EEPROM back to the replacement ECU I bought and have just wrecked.

Hey ho! Another learning curve. I will repair the copper traces and pads in due course.