pcmhacking.net

Hi all,

I need some ideas/help on how I can setup my bench to tickle a value in PCM RAM, so I can read it with PCM Logger and know that I'm getting whats expected.

I've thought about two ways, though I really don't know how to pull them off.

1) Editing a bin so it loads a specific value to RAM upon boot. (Parameter Sector maybe)
. . This would require flashing and a reboot to see the change. I'm ok with that.

2) Put a potentiometer or ??something?? on an input that has a RAM address that I could then read with PCM Logger.
. . This would not provide an EXACT value for more accurate test data ...

Both take a RAM address that I don't know ??
#1 Takes an exact bin location I don't know ??
#2 Takes a device of some type I don't know ??

Os's, either 12216125 (512k) or 12587603 (1m)

Answers, Comments, Thoughts, Ideas welcome.

Thanks

Hi all;

Per #2:
How about using an IAT sensor connected to the PCM and monitoring for a change?
perhaps someone else could tell you HOW to monitor a location as I have no clue.

Mike

Luckily both PCM's share TPS pins and ram addresses.

P01 512k
12216125 OS
12212156 OS

P59 1mb
12587603 OS

C1 - Pin 60: Low Ref
C1 - Pin 8: +5 Volt Ref
C2 - Pin 24: TPS Sensor Signal

Raw TPS Volts (0-1023 10-bit)
0xFFF2FC

Anyone know if either of them would be affected by other influences, i.e. things missing/not working, it is just a simple bench setup, PCM and DLC.

I don't have either sensor on hand, I don't mind ordering, that will take time ...

I would think the TPS would be easily spoofable if I understood how it worked for sure, it just reads 0-5v and runs it through the A/D ??

Could I just use a power supply to supply 0 to 5v on C2 - Pin 24 ??
Or would that teach the circuit that nasty smoking habit ...

Thank you!
-Enjoy

That is the raw ADC input, so not impacting by anything else. I would just get a simple 10k potentiometer and wire to those pins.

yeah pot or switch. you could switch the signal to either the 5v or low and you should get values close to 0 or 255 in ram.

That specific address is 10-bit

There is an 8-bit address, but it’s not common across the different OS’s

bubba2533 wrote: C1 - Pin 60: Low Ref
C1 - Pin 8: +5 Volt Ref
C2 - Pin 24: TPS Sensor Signal

So I don't teach this thing to smoke ...

[edit]
And I would of taught it a bad habit!

Incorrect,

10k pot hookup ... ??
Right = C1 - Pin 60: Low Ref
Middle = C1 - Pin 8: +5 Volt Ref
Left = C2 - Pin 24: TPS Sensor Signal

Correct,

10k pot hookup ... ??
Right = C1 - Pin 60: Low Ref
Middle = C2 - Pin 24: TPS Sensor Signal
Left = C1 - Pin 8: +5 Volt Ref

pot has 3 pins. one end to ground, other end to +5v, the middle one (the arm that sweeps on the resistor pad) to the sensor. If you swap both ends over you'll reverse the voltages and swap whether a left to right sweep is low to high or high to low. Just dont connect +5v and ground (low ref) directly together. Thats bad.

Oh, ok, gotcha ...

Thank you!