.

[Maddman7887]

.

[bbarney]

maybe simpler to start from scratch , post the schematic and tell us what it does

[LabVIEWguru]

Get a book on the particular processor. See where the NMI (non-maskable interrupt) vectors to. This is your start point in the program. You are going to need the addresses of all registers, ports, timers and so on from the book so you can go step-by-step with a sheet of paper and a pencil and do a hand dissassembly of the program. You will also need beer or Xanax. Unless it is something real secret, or you want an intimate knowledge of assembly language, it may be as bbarney says. Many of us have done what you want to do, and it is not a trivial matter to do.

[pickit2]

Hex file that needs converting to C.

Why C? The original would have been in Basic, and you need Asm to basic but maybe to C.

I understand i would not get the comments back.

True All named Labels & Comments are lost in complie

The device is a: PIC16F877A-IPT.
I have a Schematic design of the unit.

why not build schematic in proteus or post it here, Im sure someone will take it on.

[sohel]

first u should load on proteus. and debug step by step and see resister (bank) edit it with proper name. then make lbl to subroutine. its need time.

[TomJackson69]

If you don't know assembly then it is easier to start from scratch as bbarney already said.

Do you write any program in assembly?
Do you write any program in C?

If you know C then I think start the whole project in C. Since you already have schematic and the function of what the program does then, it is easy to write the program in C instead of assembly.

I have an idea. As you have mentioned, you wouldn't mind to pay for some one to do the job. Well, may be SONSIVRI should start to have a section for JOB BIDDING then you can post your requirement and then some of the member will bid if interesting. The payment will go through Sonsivri and bidder.

Tom

[ALLPIC]

"I have an idea. As you have mentioned, you wouldn't mind to pay for some one to do the job. Well, may be SONSIVRI should start to have a section for JOB BIDDING then you can post your requirement and then some of the member will bid if interesting. The payment will go through Sonsivri and bidder.

Tom"

Nice Idea. I like it

Or if possible in free time we all come together and make his work more simpler.

Ah Hex to C I will not prefear, I will see schematics and if possible I will add something new so that product will be different

[Maddman7887]

.

[bbarney]

After a quick look at the schematic you would sure benefit by moving up to an 18f series pic with usb and preferably canbus capabilty of which there are a lot of choices, just something to think about staying with an 16f877 with those other oics avaible would be foolish if your looking to expand it's usability.have you ever visited scantool.net http://www.scantool.net/

[Maddman7887]

.

[sphinx]

well if i am not to wrong here i think this is some sort of modem/adaptor to car ECU unit,
 but for that to work there is also the need of pc software for it work properly. this unit
 might work with several brands of car or just a few depending on computer software and
 hardware of adaptor.

there are different systems on the market is it for older or newer cars, since some newer
 cars have ODB-II. but without the software interface which might be made specificly to this
 adaptor, there might be som generic software as well but i am not into deep into that so i
 dont know.

to me this adaptor without computer software or any other info i think its really hard to make
 it work. but you might have software and/or more info on it that works with this unit, otherwise
 it to me looks like a black box that you need to figure out and then make some software to it,
 and thats lot of work, might even get pretty complicated as well.

i remember that elektor had an odb-II adaptor as a project which migh help on continuing developing
 this unit.

best of luch on your project.
 regards mike

[bbarney]

sphinx
your right about the OBII and needing a computer hookup via usb or serial (check my link scantool) , that's basically what this is -- the actual reading of the codes is a standard thing that's the OBII standard that is almost the same world wide but not quite some japanese cars are a lttle different with their code and protocol but most use the same so you build a simple code reader ( checkout the Elm chip) than the PC software which there are alot of free one;s interperts the code and tells you in an easier to understand format what the code is.
Bi-directional isn't as common but most of them are to some degree but limited to turning off trouble codes or the check enigne light the really exspensive ones allow you to change shift points in the transmission and  turn on ABS solenoids to test them etc
If one knows the codes it's just a matter of making the software read the canbus and convert the bits to english  sounds simple right 
heres some links and microchip now has a canbus analizer that looks like a pickit2 that would be very cheap and handy if your really interested in learning this
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1406&dDocName=en546534
http://www.interfacebus.com/Design_Connector_CAN.html
http://www.vector.com/va_index_us.html
http://www.sonsivri.com/forum/index.php?topic=5505.0