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Modified Lisa Backplane

NeXT

NeXT

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Last Lisa thread by me. I promise! Seriously guys! :mrgreen:

So my lisa runs, My lisa displays something and right off the bat, the Lisa is booting the LOS installer off the floppy drive.
Unfortunately I can't get the Lisa talking to the ProFile. I got it under unknown conditions and it needed a recap but otherwise you turn it on and the drive quietly spins up and goes READY but the Lisa and the installer can't see it. I tried one of Apple's ProFile cables and a cable I built for the occasion. A brief blip where once and only once did it give an error 82 but otherwise no dice.
When I had the card cage torn down for battery cleaning I noticed that someone had been screwing around with the parallel port.

CRW_7115.jpg

CRW_7117.jpg


I'm aware that the Lisa 2 conversion pulls resistors off the I/O board but I don't seem to recall anything about the parallel port needing drastic modifications. It looks like all the pins have been rerouted through 330 ohm resistors and pin 13 is completely cut. Does anyone else have this on their Lisa?
 
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Hmm..if I remember I'll check this tonight.

I have a similar problem with my 10MB Profile. It spins up and seems to got through the self check just fine. The Lisa does know a profile is attached. If you go to access it, lights spin, things clatter but it comes up with an error...not one of the helpful ones but one of those undefined causes ones (I can't remember the number off the top of my head). I've been through all the literature and stuff on the web. I've even tried a low level format with the tools that are now available but not joy (although I may have needed a special chip for this anyway..which I don't have). I did some initial diagnosis following the signals from the connector through the various parts of the board and they seem ok.

In the end I abandoned the repair.

These profiles have a lot of circuitry and it could be anything. The fact that it self-checks ok means that something is working anyway. Sometimes though, you just have to admit defeat. (at least for now!). The ProFile still looks good as a prop and I do have an X/Profile card so I can run the Office Suite.

I might get back to it one day.

Tez
 
You can't Low Level format a ProFile unless you have the LLF ROM, regardless if you have the Apple III and the utility. There is not enough space on one ROM for both the instructions for regular disk use and the formatting so it was spread over two chips you swapped before and after the format.
Error 82 is "Bad Response From Disk" which meant it knew something was there but it couldn't use whatever was there. I really need another Apple system that can handle a ProFile to confirm if it's the drive or not. Seeing the prices for Profiles right now (or even emulators for that matter) makes me want to try every option first.
 
NeXT said:
I'm aware that the Lisa 2 conversion pulls resistors off the I/O board but I don't seem to recall anything about the parallel port needing drastic modifications. It looks like all the pins have been rerouted through 330 ohm resistors and pin 13 is completely cut. Does anyone else have this on their Lisa?
Click to expand...

Hmm...interesting. On one of my Lisa 2/5 motherboards (the motherboard that does not work for some unknown reason) I have no resistors on the parallel port, and on the other Lisa 2/5 motherboard (the one in the working Lisa) I have a bank of them just like yours?.

Tez
 
NeXT said:
You can't Low Level format a ProFile unless you have the LLF ROM, regardless if you have the Apple III and the utility.
Click to expand...

BLU claims it's able to do it directly from the Lisa...

I'm planning to try it out this weekend. Me too I'm experiencing problems with a Profile I recently acquired: passes self-test (first 75% quite straightforward, last part takes a lot of time but in the end it becomes ready) but no machine seems to be able to communicate with it: invisible to a Lisa 2/10 with parallel card, I/O error with Apple III and Apple IIe with the proper interface kit... :angry:

Mine is a 10MB, will try LLF with BLU and if it still doesn't work I'll try with another disk taken off an XT. I don't have the original cable though... I'm using a straight male DB25.
 
As far as I know and read the BLU manual also BLU needs the Formatter ROM + Z8 Chip.. I will try this the next week too.
 
Hmm, so I'm not the only one then with this. I wonder what on earth they were doing it for?
I would check the schematics for the Motherboard however the site I frequented for schematics went down during Sandy and has not been up since and Bitsavers doesn't seem to have them either, only photos of the Lisa 2/10's motherboard.
I'm planning to try it out this weekend. Me too I'm experiencing problems with a Profile I recently acquired: passes self-test (first 75% quite straightforward, last part takes a lot of time but in the end it becomes ready) but no machine seems to be able to communicate with it: invisible to a Lisa 2/10 with parallel card, I/O error with Apple III and Apple IIe with the proper interface kit...
Click to expand...
I'm curious if in your case something in the parallel interface might be blown as it sounds like the disk itself is mechanically okay. Actually, I wonder if both of ours might of flaked out. Still too early to be positive. The schematics for the control board are over at bitsavers.
 
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alker said:
As far as I know and read the BLU manual also BLU needs the Formatter ROM + Z8 Chip.. I will try this the next week too.
Click to expand...

One question, can this formatter ROM be burned into an EPROM? Is it then just a matter of removing the Z8 and dropping the formatting (EP)ROM in? I'm confused about this.

Tez
 
Gabriele72 said:
I'm planning to try it out this weekend. Me too I'm experiencing problems with a Profile I recently acquired: passes self-test (first 75% quite straightforward, last part takes a lot of time but in the end it becomes ready....)
Click to expand...

This is exactly the symptoms mine has too on the self-check EXCEPT at least the machine can see the drive (and when it tries to boot from it it comes up with a big red cross over the icon plus the unhelpful error code). Mine is also a 10MB one.

I too have a non-Lisa DB 25 cable with all the pins present. The proper Lisa cable has one pin missing but that pin's socket isn't connected to the board anyway, I figure having that pin present shouldn't matter.

Tez
 
@Alker
yes, you're right, I did skip that part when reading the manual in too much excitement :)

@Tezza
The EPROM that sits on the Z8 formatter is a standard 2716. If you have the Z8 with the piggyback socket in your Profile then I think you only need a dump of the EPROM and you're ready to go, otherwise... I don't know if a spare Z8 chip of that kind would do. We should find out if the Z8 internal ROM is customized for use with the Profile.

Alker, perhaps you could make a dump of that 2716 for us?
 
Gabriele72 said:
@Tezza
The EPROM that sits on the Z8 formatter is a standard 2716. If you have the Z8 with the piggyback socket in your Profile then I think you only need a dump of the EPROM and you're ready to go, otherwise... I don't know if a spare Z8 chip of that kind would do. We should find out if the Z8 internal ROM is customized for use with the Profile.
Click to expand...

Hmm...I'm not even sure where the "Z8" is in my 10MB Profile. There is a large chip labelled 341-0287 which I believe is the 10MB Profile ROM. I THINK this is the equivalent of the Z8 chip for this Profile (is it?). There is certainly no piggyback socket on it anyway (or on any of the other ICs in the Profile boards).

Terry
 
tezza said:
Hmm...I'm not even sure where the "Z8" is in my 10MB Profile. There is a large chip labelled 341-0287 which I believe is the 10MB Profile ROM. I THINK this is the equivalent of the Z8 chip for this Profile (is it?). There is certainly no piggyback socket on it anyway (or on any of the other ICs in the Profile boards).
Terry
Click to expand...

Facing the Profile, it's the 40-pin chip in the upper right corner. The golden Z8 is sometimes found in the 5MB Profile, mine it's 10MB and has the same black plastic version as yours.

It could be interesting to take a look at the EPROM content, to see what it does... and maybe the Z8 formatter behaviour could be emulated with a modern microcontroller.
Perhaps using the modern Z8 evolution itself, the "Z8 Encore" ?

EDIT:
Wait a minute... I do know where you could find a piggyback Z8... Tez, take a look at the upper board of the Widget controller, what's on it ?
 
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Gabriele72 said:
Wait a minute... I do know where you could find a piggyback Z8... Tez, take a look at the upper board of the Widget controller, what's on it ?
Click to expand...

Some of them have the Z8 as well, some have another black plastic 8439 chip named "LIZZY".
There does appear to be a guy on ebay right now selling NOS Z8's for $50 each.

Also, yeah, the Z8 in a profile goes where the Zilog SR0081 is located where the Z8 would normally be.

Edited: on topic, I have noticed that before the Profile receives lines from the parallel port they all pass through two MDP1603-101G resistor networks. The schematics show that they should both be rated for 330 ohm however the datasheet conflicts with this. If by chance either of these were blown this would explain why the Lisa can't talk to the drive.
 
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I ended up checking the connections starting at the DB25 port on the ProFile to the individual chips on the I/O board and there are no broken connections so that is not the reason why my ProFile isn't detected.
 
Gabriele72 said:
EDIT:
Wait a minute... I do know where you could find a piggyback Z8... Tez, take a look at the upper board of the Widget controller, what's on it ?
Click to expand...

Yes there is a piggyback Z8 there. But that's for the Widget isn't it? Would that work on a Lisa ProFile 10MB? They would be different, wouldn't they?

Tez
 
yes the Z8 from the widget should work but you'd need the 10MB formatter ROM back on the Z8.. I have the 5MB formatter ROM but I'm also searching for the 10MB ROM chip
 
I don't know anything about the ProFile drive, but I can tell you that my Lisa 2 which I bought from Sun Remarketing in the 80's had a parallel port with resistors that looked just like the first picture in this thread. I only ever booted that machine from a floppy and never actually tried to use the parallel port for anything.
 
BUMP

I did eventually determine that the corrosion damage had opened all of the resistors and removing and bridging the modifications brought back the parallel port.
Still though, here I am ten years later and I don't know what the purpose of the resistors was for. I was smart enough to note where the resistors used to go and there was one cut trace. Port protection?
 
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