28C256 in VN/VP ECM

[simc]

Hi All,
I could not seem to find any info on this topic (I may have missed it) but I thought I would share it quickly. I recently tried a 28C256 (EEPROM) in place of a 27c128(EPROM), for a VP ECM. All I needed to do was switch pin 1 and pin 27, and away she went.

I know it's still far from real time tuning, but still easier the playing around with a UV eraser. The 28C256 is nice and easy to get a hold of too.

[kelvin]

I want to do the same, could you just confirm.
I've made up an adaptor that plugs into the memcal and then slips into the ZIF socket on the programmer. Are you saying if I unsolder pins 1 and 27 and swap them over, that's all I need to do. And select 28c256 as the device on the programmer. Sounds so easy.

[charlay86]

I think what he means is:
for a 28C256 to work in the VN/VP PCM pins 1 & 27 need to be swapped.

so if you swap those pins and then try to program it as a 28C256 device, it will not be able to program it because the pins will be in a different position to what the programmer expects. your adaptor would need to swap the pins back to the original location to be able to program it.

[kelvin]

Got it !!
Thanks, I'll get a spare memcal and give it a go.

[simc]

Charlay86 is on the money!