Car OBD to Psp

Squall333 · Post by **Squall333** » Sat Sep 23, 2006 2:52 pm

Im trying to collect data from my cars OBD1.5 port to my psp iv been doing research and it seems all i need is a ground and a data line from the obd port.

Whats the easiest way to do this?

I also found this and im not sure if its needed
Edit: i found this

Squall333 · Post by **Squall333** » Sun Sep 24, 2006 12:08 pm

Pretty much what im asking is how can i make a setup to recieve any kind of data from the obd.

adrahil · Post by **adrahil** » Sun Sep 24, 2006 7:04 pm

Not sure about how to do this, but I'm sure that 12V will fry your psp....

harleyg · Post by **harleyg** » Sun Sep 24, 2006 8:14 pm

PSP is 5v... i think.

adrahil · Post by **adrahil** » Sun Sep 24, 2006 8:53 pm

it is :)

Squall333 · Post by **Squall333** » Mon Sep 25, 2006 1:33 pm

I dont even know what that 12 v is for

Squall333 · Post by **Squall333** » Mon Sep 25, 2006 1:48 pm

How do i set my psp to record any data coming across the line?

dsn · Post by **dsn** » Mon Sep 25, 2006 3:25 pm

Do not wire your PSP to that. You will destroy it.

You need to figure out a way to convert the 12v signal to 5v.

If I remember correctly, OBD is more than just a simple serial protocol, it's more like a network architecture where each device in the car has an address and can be queried directly. But don't quote me on that. In any case, it sounds like you need to do two things to make this a reality:

- Learn as much as you possibly can about OBD. I don't think anyone here knows much about it (judging by the dearth of replies); try a hobbyist mechanics' forum instead. They'd probably eat this up.
- Learn more about electronics in general, and the PSP's serial port in particular. There are lots of topics here that talk about the serial port, almost all of which will repeat the warning I made at the beginning of this post, and which I will repeat here: don't attach 12v to your PSP!

Oh, and if you figure this out, I will worship you. :-)

Squall333 · Post by **Squall333** » Tue Sep 26, 2006 12:39 pm

There are free programs out there that work with obd 1 so its a matter of porting them i guess. As for the 12 to 5 v conversion ill have to do some research

Squall333 · Post by **Squall333** » Fri Sep 29, 2006 12:46 pm

Now how do i adjust the baud rates to be the same?

Art · Post by **Art** » Sat Oct 14, 2006 3:15 pm

oops.. deleted.

digihoe · Post by **digihoe** » Mon Oct 16, 2006 7:30 am

harleyg wrote:PSP is 5v... i think.

I thought it was 2.5v... Silly me...

Squall333 · Post by **Squall333** » Tue Oct 17, 2006 12:08 pm

Ok so i got all the stuff i need to do this. I got a 5 v regulator and im gonna check it with a multimeter after its all together. As long as the data is 5v or below im good right?

Squall333 · Post by **Squall333** » Sat Oct 21, 2006 6:41 am

Everything im reading says the psp is 2.5v

Wally · Post by **Wally** » Sat Oct 21, 2006 8:22 pm

Its 5 volts according to sony...

jimparis · Post by **jimparis** » Sun Oct 22, 2006 1:59 am

The headphone jack (= sio port) is 2.5v, just measure it and see. Sony has never said anything about the headphone jack specs.

Squall333 · Post by **Squall333** » Sun Oct 22, 2006 7:26 am

Im gonna go with jimparis on this one

Zianna123 · Post by **Zianna123** » Thu Oct 26, 2006 9:52 pm

just for interest sake why would you be using transistors to do the level conversion. would an ic option (MAX232, MAX233) not be a better option.

also the PSP is most defenatly 2.5 vault. using a level converter like the MAX232 would sort the 12V to 2.5 no proplem, as it is a true TTL to line converter.

the power schematic you supplied will do a decent job, just keep in mind that it has no over current / volt protection. a car is a very unreliable source of power, espicialy when cranking the motor, and reving. so i would revise that circuit to have a 12V over voltage low drop out regulator infront of the 78l05 .. you dont wanna go frying your poor ol psp, the first time you start the motor.

i would not howver use that data cable at all, all that circuit is doing is switching the RX and TX. but still providing 12V on the PSP side.. while this may have worked on older PC's almost all new PC's and laptops now use the 5v logic. check out MAxims site for the spec sheet on the max232, Max233 level converter, she is your friend and realy cheep.. hell i think they even give samples away...

anyhow just my 2cents worth.. nice project tho, have you started on the software tho?

digihoe · Post by **digihoe** » Sun Oct 29, 2006 5:51 am

Yes, it looks like a Mbus interface, you should be able to do the switching with a zener diode... I think it would work with a MAX233 and a 12v zener...

Try to locate an other schematic for that interface...

Good luck...

Charles · Post by **Charles** » Wed Nov 01, 2006 2:48 am

PSP serial page:

http://www.luaplayer.org/sio/

http://www.hitmen-console.org/

Has a good PSP document with info on the serial port.

Anyone in here into boating? The PSP would make a great display for a fishfinder/depth sounder. Do you think the PSP has more or less processing power than a high end device like a Humminbird 987C?

charliex · Post by **charliex** » Wed Nov 15, 2006 4:49 am

OBD is just a serial protocol as is OBD II , sounds like the above poster is thinking of CAN BUS.

you send packets out with the data requested , you receive packets back with the reply.

ALDL is usually 8192 baud though, which might be an isssue

http://www.techedge.com.au/vehicle/aldl8192/8192hw.htm

the two transistor variant works ok on some cars, but not all.

OBD varies wildly, OBD II is a slightly better standard, ISO 9141-2

i presume this is for gm 94/95 or mitsuis? obd 1.5 isn't that widepsread.