1994 Corvette EEHack DataLog Review

[steveo]

the only difference between getting ready for read or write is we don't upload the code to set VPP voltage for read (since it's not necessary), i can't imagine that has any effect

[spfautsch]

It has worked for me, I have a file named 'vette-eehack-read-0521.bin' in my 2016 logs and bins folder. I had no other reason to do a read other than to test eehack's read function.

If there's some timer that needs to expire in the ecu it may be possible to wait a few seconds after launching the flash window before enabling any of those functions so the key seed issue doesn't happen to others.

[kur4o]

The timer is set at pcm reset and until it expires, the pcm can`t access mode 13. It is also reloaded at some point, maybe to prevent mode 13 at engine running.

I suspect it to be 8-10 seconds timout after reset is done, before you can access security mode. Rearmed on wrong key.

There are some other timers too. One of it is the time between seed response and key recieved. The purpose of the others is not so clear.

[steveo]

kur4o could we get around that? dump the timer ram to see if its active and wait if it is? whats its location?

[spfautsch]

Thanks kur4o - that was it. Seemed to be about 10s from key on. Three reads in a row, no problems. As I mentioned steveo if we disabled all the buttons on the flash window for 10s after initialization that would take care of it. Or even easier just make the error message more descriptive along the lines of waiting longer. Had I known about the timers, well I can follow directions. Those who cannot will ask questions regardless.

RISK81 -

I feel confident your issue will be resolved with a diy cable.

[RISK81]

Thanks kur4o - that was it. Seemed to be about 10s from key on. Three reads in a row, no problems. As I mentioned steveo if we disabled all the buttons on the flash window for 10s after initialization that would take care of it. Or even easier just make the error message more descriptive along the lines of waiting longer. Had I known about the timers, well I can follow directions. Those who cannot will ask questions regardless.

RISK81 -

I feel confident your issue will be resolved with a diy cable.

Guys, Thanks for investigating the READ issue. As of now I have placed an order for the Adafruit IC bridge USB-UART Module (PN_1528-2591-ND) and also the Adafruit FTDI Serial TTL-232 USB Cable (PN_1528-1644-ND) through Digi-Key. Once the units are received, I'll construct a basic temporary cable and terminate to the mentioned pins listed above and post the results regarding the read function after a 10 sec delay from key-on.

If this checks-out I like the idea of terminating a permanent cable to the back-side of the ALDL connector at the specified pins with appropriate strain-relief for future flashing / data-logging.

Thanks again for everyone looking into this matter.

[RISK81]

All systems go!! I have successfully downloaded my PCM tune without an error via EEHack. It was the adapter all along (thanks to everyone). First attempt was with the FTDI serial TTL-232 USB cable - no success... Second attempt was with the AdaFruit board (PN-P284B) and a dedicated OBD2 blank connector with pins 4 & 9. Thanks again to everyone! 20190513_204326.jpg
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