ITPS Timing Problem

**Entcee** · 04-20-2004, 08:30 PM

I am having a problem with the ITPS. Nat with mp3car.com was nice enough to send me another one, but it does the same thing. Anyone else have this problem?

With everything off, power supply, computer, everything.
I touch the red wire (switched input) to a power source,
the 12v output turns on, but the computer does not.

Now if I power the computer with another source, 1 second
after I touch the red wire (switched input) to a power source,
the computer turns on, then 3 seconds later, the 12v output
from the ITPS turns on.

So basically, the ITPS is sending the pulse to turn the
computer on BEFORE the 12 rail turns on instead of 1
second after.

Any ideas?

**Ricky327** · 04-20-2004, 11:20 PM

How is the permanent +12V supply for the ITPS connected?

**Entcee** · 04-20-2004, 11:27 PM

I am using a DC power supply to test it that supplies 13.8v and 4-6 amps.
I have the white wire goung to the + terminal and the black wire going to the - terminal.

**Ricky327** · 04-20-2004, 11:36 PM

Yes but dont it supposed to have 3 wires altogether?

1) Permanent +12V
2) Switched +12V
3) Ground

**Entcee** · 04-20-2004, 11:38 PM

Yes, I touch the red wire (switched) to the + terminal on the power supply (same as the white wire) and I hold it there while the "car is on".

**Ricky327** · 04-20-2004, 11:53 PM

Was the white wire already connected to +12V and the ITPS have settled down before you touch the red wire to +12V to trigger?

I just get an feeling the ITPS PIC only get powered up when you touch the red wire to +12V (im assuming this is the trigger wire). From that then the white wire is your permanent +12V supply?

Try making the red wire the permanent +12V and the white wire as your trigger.

It seems the ITPS triggers the PC as soon as you power up...its a glitch on the PIC design and the ITPS firmware.

**Ricky327** · 04-20-2004, 11:58 PM

If you tried it all then I guess theres something else wrong with your setup. I dont think its the ITPS as its already been replaced as you said.

Good luck and let us know what happened

**Entcee** · 04-22-2004, 12:13 PM

Sorry it has been so long, I did not get an email that anyone had replied.

Yes, the white wire was already connected to the +12v source and sitting there, then I touch the red wire (switched)

The white wire is definitely the constant power, and the red is the switched. It does not work at all if I switch them around (plus the documentation says it is this way.)

I really think the firmware is written wrong. The may have put in 1 second for the delay before the pulse is sent (because it is supposed to delay one second after the 12v rail turns on) but they should have put the delay as 5 second because the 12v rail turns on 4 seconds after trigger, so the pulse would be sent 5 seconds after trigger.

You know of anyone who can change the delays for me?

**dug1967** · 04-22-2004, 02:11 PM

Originally Posted by Entcee

You know of anyone who can change the delays for me?

Well Entcee.... in a little bit here hopefuly I will have the capability to burn new PICs for the ITPS with any time delays you want... I got a PIC programmer coming from Austrailia (maybe receive next week) and got some PICs from DigiKey yesterday....

I have never done any PIC programming, but the ITPS code is open source and available from their website, so hopefully it will be change a few variables and be done....

I need to up the delay time before the signal is sent to the MB to turn on, because I let my car sit about 10 to 15 sec. after I turn the ignition on, before I crank it to let the ECM settle in....

I will let you know if I have any luck...

**Entcee** · 04-22-2004, 02:20 PM

If you are successful, I would not mind paying you to program one for me.
Although the factory settings (if they would work) are OK for me, I would like my own delays.

Keep me informed.