Cant Write To My NVRAM

[festy]

Just noticed your log says no response to the writes - is that normal for a write protected nvram or would you still get a response of some sort?

[VL400]

I stand corrected, there is no mention in the datasheet of write protecting on low internal battery, the DS1210 has a feature where it blocks the second memory cycle to warn of a low voltage but it's not an actual write protect mode. That must have been what I was thinking of...

And that also explains why I've never seen a WP'd NVRAM, but have seen a couple that program and verify fine, but lose their memory as soon as they're removed from the programmer.

They will be read-only if the ECU's 5v supply drops below 4.5v (-Y) or 4.75v (-AB) but I think you'd have bigger problems in that case...

It would be really nice if the DS RAM chip had some smarts like Flash memory where you can request info from the chip (locks, type etc). Would be nice to be able to interrogate the battery status.

Just noticed your log says no response to the writes - is that normal for a write protected nvram or would you still get a response of some sort?

Yeah it is..

The way the flashtool fails to write indicates that the ECU is in read only mode to the NVRAM (it does a test on boot), it black holes all attempts to write to it so TP/flashtool software fails. Even writing a 100% identical cal to the ECU will fail, the 12P bin checks the NVRAM status before any attempt to write data.

[Dylan]

I have found the problem and now can write. I has bent a pin over on the socket on the ecu board. And turn out its where the write wire connects to underneath.
I was mucking around swapping my NVRAM and a mates one last weekend. look like when i went home and re fitted mine i bent the pin.

Appreciate everyones help and VL400's offer for me to send it to him. Its the support like this you dont get anywhere else.
Thanks!

[Jayme]

yep.... done that before myself

[Dylan]

That's good to hear, still feel stupid though

[Holden202T]

I'd say we all have!

I have a socket on my nvram chip cable tied to it to remove from the memcal board as I almost snapped an nvram pin removing it once!! that was a scary moment!

[VL400]

Your not the first and wont be the last for that! Glad its all sorted