pureroundcircle

I'm having trouble burning a custom chip.

I have a chip burner and have BIN files for the chips. In the past I've had a couple performance chips and I made BIN files and edited the timing, and wastegate frequency maps. I can successfully burn the modified chip. (at least my programmer says it verifies ok).

I've been told in the past I can use eeproms in place of the original eprom chips and if I use chips of additional size the ECU will just disregard the info after the address it is programmed to read up through.

The original chip in the mac-11b in my car is a 27c64, I'm trying to use an 27sf512 in its place. The car does not start with my burned chip. Does anyone know if this is an addressing issue, or ? I just don't know all that much about these chips to know if I need to try and burn the data at the end of chip or what so it is correctly addressed, or some step i've missed?

Thanks

MarkPan

You either have to tie the additional address lines low, or just duplicate the bin file over and over. (A13 - A15).

So 512/64 = 8... make a bin that contains the old bin file 8x in a row, this way no matter what the high address lines are, the data on the area the microcontroller can read is the same.

Does make sense?

If you want to get fancy you can have switches on the high lines, and 8 different bins concatenated... if you want different maps or somesuch.

Some of those 'unused' pins might be tied high/low in the MAC (don't remember..), if so, you can see what the score is and map it right.

eg. if A15 is high, and A13 and A14 are low, the bin should start at 0x8000, instead of 0x0000 (if you were using a 2764).

pureroundcircle

I'll try repeating the code 8x and see if this does the trick. Hopefully I've got time this weekend to try this.

I have very little experience burning chips or programming so I don't think I'm up to the task of mapping anything. About the only thing i've done other than this is program some pic chips with picbasic to do simple tasks.

Thanks!

pureroundcircle

Thanks! I now have a working chip on a 27sf512. You wouldn't happen to know how to correct the checksum would you?

I've read in the past I need to verify my checksum stays the same from chip to chip and modify the last line of code to keep the checksum the same. The program I'm using "010 editor" has about 10 different checksum calculation methods. I'm not sure which one I'm trying to match.

But also my stock vs. QLCC vs. @bennett chips have different checksums.

Guess I'm a little confused yet.

Thanks,