Nistune Forums

I need the following hardware buzz outs on multimeter against GND (pin 14) on the 28 pin EPROM socket for Z31/Z32

R31:
/CE PIN 20 does not buzz, connected to address selector (MB13T111 pin 14)
/OE PIN 22 buzzes to GND (0 ohms)

R32:
/CE PIN 20 buzzes to GND (0 ohms)
/OE PIN 22 does not buzz, connected to address selector)

Z31: ??? please confirm if same as R31

Z32: ??? please confirm if same as R32

From the NVRAM diagram provided on the ztech forums, the /OE line is not used for address selection, but the /CE (/CS) line on pin 20 is. this appears different to the R32. it could mean a different jumper on the Z32 version of the tuning board

Does it matter if this is done wth the chip in or out?

no can be done with chip in. if there is conformal coating over the chip, you will need to put the probes through the coating to get conduction

so need to measure pin 14-20 and pin 14-22

i suspect our R31/Z31s 6802 based ecus are the only ones which use /CE line to read the ERPOM...

Ok. Here's the results of my quick test.

M30, Z32, Q45 ecu...
Neither pin 20 or pin 22 buzz to pin 14.

Z31 ecu...
Pin 20 no buzz
Pin 22 I get a buzz

thanks for doing that... im really suprised the pins on the Z32 etc dont buzz to ground

btw i had to really push the probes through the conformal coating on the EPROM pins to get a reading on the CA18 ECU i just did

CA18DET - pin 14 buzzes to pin 20 (/CE)

what i might do is ignore the /CE and /OE eprom lines and just get the readings from the 6303 processor directly since these lines are filtered out when doing writes anyway by the address decoding circuitry

If/when I get time to try again I'll do the test from the back side on a fresh solder joint. I did push pretty hard and scraped a bit too. I know the probe was grounded to pin 14 because I buzzed it to another ground on the ecu board. I was a bit doubtful of my results because you were expecting one of the pins to buzz. All three 6303 ecus were the same though so I'm tempted to say they are right. Maybe I just have very bad luck. Hehe.

someone else on ztechz tried it out and got the same result. i've got a work around anyway (not to use either of these lines). seems to work with NVRAM so far

That someone was me...LOL

well i got Z32 ecu running nvram now as with the R32 ecu using a prototype board. all looks good. that consult code patch is over a year old now and still hasn't got out the door yet

Thats great,, let me know when the boards are inn and programmed, will be nice to be able to "pitch" the emulator...