Calling All Stooges

Yes. I'm guessing the large chip that looks like an NEC chip is an EPROM or PLCC. If it is an EPROM, we just need to find a reader/programmer. I'm guessing that the brown coating is covering up a couple of op-amp circuits used as comparators. Will the brown coating scratch off? I know some deprocessing labs that can probably remove it for a small fee. I also work with many PCB fab houses, so we should be able to build the circuit boards in quantities.

One issue though is that I don't have a 348 to look at, so I don't know all of the functions of this unit. My F355 HVAC unit is completely different and apparently much simpler.

Another issue is the legality of copying an EPROM program owned by Ferrari. It may be that we would have to come up with our own state diagram and create our own program. It has been about 20 years since I've done anything like that. From what I remember, it wasn't unreasonably difficult though.

 

Each Ferrari 348 owner has, by default, legally purchased 1 copy of the firmware. So long as that firmware is only used in said Ferrari 348, I don't see a legal issue.

1 copy in use per owner (well, if you've got 2 348's then you should be able to use 2 copies) at any one given time.

In contrast, if you were copying the proprietary firmware to use in multiple, non-Ferrari 348 vehicles, then there would be a legal issue.



*I'm not a lawyer and the above is not legal advice, just an opinion based on software logic such as being able to use one Operating System on 1 computer.

 

Well we still don't really know what is wrong with the oem units. Perhaps the eprom chip is fine. Many we can avoid the whole issue by only reusing the eprom chip if that chip actually is ok. We all know how wonderfull the 348 electricals are but I think we can all agree and DaveHelms has basically proven that the problems are not in the ecu's (eprom chip being most central) but the execution after.

 

Excellent point, FBB.

 

Well I've got 75% of the system transfered to a simplified schematic. Daniel, what are the numbers on the big chip? I took a close up of my chip but that picture is on a computer that crashed! I've got the fancy reader/programmer but I think it is a microcontroller with on board ROM which makes it complicated. I can de-cap those chips at the wafer fab if you send one to me but the sulfuric acid is probably going to wipe out the #. I think I could put it on the wafer lapper tool and thin that stuff down to the point where a diluted sulfuric mixture will reveal the #'s. I think Tom's right about the op amps. You've got 3 main temp sensors that take up six out of the 26 pins and some sort of differetial sensor is needed. The other chip might be an A/D but that's probably built into the larger chip. One of the pins is ground side control for the coolant pump and if that thing is seized you've got an over current situation in the controller. The part with the heat sink may be for that as most of the other pins control relays. What are the common failures and their symptoms? There are also about 10 connectors which could wreak havoc. My controler seems to have a problem in it's ability to deliver the PWM signal to the blower speed controller. The fan is intermitant as hell I was in the process of mapping the whole system with the intent of programming a microcontroller or a FPGA. Tom we are close enough that we could use my car as a test bench. This system was to smart for what was built around it when it comes to poor Ferrari conectors.

 

If you are talking about removing the brown stuff, I would try an exacto knife first. You'd be amazed how much money I've saved by using my utility knife instead of sending chips off the the lab to be deprocessed.

If the NEC chip is still good, then maybe we can just fab everything else and reuse the chip as stated in a previous message above.

If you have a schematic, I have a couple of PCB vendors that I work with that may be able to give us some good pricing for layout, fab, and assembly.

Tom

 

The large brown board is what we used to call a hybrid device in the electronic manufacturing industry. I guess its custom made and is fitted out with surface mount components. You may be able to determine what the ICs are, but the small SMT components which will be resistors and capacitors will be very difficult.

Just my thoughts

 

Yep, the NEC chip is a microcontroller. At least we can still get them. MPD78CP14G-36 - 8-BIT SINGLE-CHIP MICROCONTROLLER - NEC

As far as the brown board, the surface mounted caps and resistors could be removed and measured.

 

What is visible is the parts for a power supply and a character controller (the NEC Chip) to drive the keys and displays. The board that is covered in the brown "goo" is the "brains" of the circuit. I'm sure you'll find an EPROM and a microprocessor underneath the physical copy protection covering.

In the '80s this method was quite common to prevent simple circuit boards from being copied and still be able to build them using some custom code and off the shelf parts. I'm sure everything on there would have cost <USD10 on a radioshack catalog from the era...

IF you want to mess with it, you will have to use abrasives to remove the brown coating, and I can tell you from having tried on many other things (I made my own Apple II clone back in the "days") you run a 99% chance of destroying it before getting any information printed on the components, let alone the circuitry.

I'll bet you after fixing about 3 of these unites, that 9 out of 10 problems are due to dry solder joints on the accessible parts. Secondly I'd replace the capacitors.

Marco

 

Nine years later...

Daniel, any progress? Miracles? Used units are scarcer and prices are shooting upwards.

:fingers-crossed:

 

Not to hijack the thread, but if you have the catalog if every connector, any idea of where i can get a plug the fits the Zivan charger plug for an early 612? Id like a plug that i can convert to a CTEK charger.

After i posted, i just saw the age of this thread.