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Piggybacked Zilog Z8
- Thread starter CelGen
- Start date
ProFile hard disks cannot low-level format on their own. There was not enough space in ROM to fit the operating code and the formatter. Second issue is that unless you had an early ProFile drive they all shipped with a more conventional black plastic DIP package where the ROM was an internal mask ROM.
This is the ceramic "ROMless" version of the Z8 microcontroller where the code was supplied on an easily interchangeable EPROM that plugged in a piggybacked socket. I simply burn the formatter image to a 2732, drop it on the Z8, drop that into the Z8 socket on the ProFile along with jumpering two pins and you are ready to LLF and recertify an ST-506 or ST-412 HDA.
Because they are both purple ceramic and gold capped, the gold bugs try to sell them for crazy amounts. This one only cost $30.
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Correction: You can low level format all the 5MB ProFiles whenever you want. The 10MB ProFile requires a Z8613 piggyback Z8. If you need to borrow it, let me knowNo longer have to bum the chip off snuci.
Now I can do work on my ProFile (or any other) whenever I want.
EDIT: Sorry, not sure why a quick edit quoted my original post instead of just editing the original.Correction: You can low level format all the 5MB ProFiles you want, whenever you want. The 10MB ProFile requires a Z8613 piggyback Z8. If you need to borrow it, let me know
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Correction: You can low level format all the 5MB ProFiles whenever you want. The 10MB ProFile requires a Z8613 piggyback Z8. If you need to borrow it, let me know
No....
.....No. I totally did not just mix my numbers up like that...
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That is just plain weird. I've seen a lot of odd electronics, but never a chip-on-chip socket like that.
Actually CelGen, you did well, even if you can't use this one for your 10MB ProFile. It is a collectible chip at least. The two I bought I got in the $20 range also. You just have to be patient. I believe I found mine by looking at the photos posted for Z8's that didn't list the part numbers properly. If the ad has the part number, they will not go cheap.
To provide further details, these are known as "Z8 protopacks". From http://verhoeven272.nl/fruttenboel/softy//z8techman2.html
I'm not sure if I've ever heard of early Z8613's in 10 MB ProFiles. As I understand it, 10MB ProFiles, by themselves, are hard to find.
The obvious difference between the two piggy back chips is that one utilizes 2k and the other utilizes 4k in "on chip" (literally) memory. My "2K" image is a 4k chip with 2k copied twice and burned as a 4k image. I don't have something that will burn 2716s yet.
To provide further details, these are known as "Z8 protopacks". From http://verhoeven272.nl/fruttenboel/softy//z8techman2.html
Very early 5MB ProFiles had the Z8 protopacks in place with running ROM on EPROMs. When the Z8601's were finalized, they came with those and the "piggy back" chips were no longer used because they were more expensive. Low Level Format versions were never produced in final versions because the software on ROM should have never left the factory. Thanks to the code being released and software called BLU, we can re-low level format our ProFiles.
I'm not sure if I've ever heard of early Z8613's in 10 MB ProFiles. As I understand it, 10MB ProFiles, by themselves, are hard to find.
The obvious difference between the two piggy back chips is that one utilizes 2k and the other utilizes 4k in "on chip" (literally) memory. My "2K" image is a 4k chip with 2k copied twice and burned as a 4k image. I don't have something that will burn 2716s yet.
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You should of mentioned. My Willem station can do 2716's...or I think I did. I don't immediately have at hand the SCSI card for my Lisa.
Anyways, I can hold onto the chip regardless should for some random reason I come across a 5mb Profile or someone out on this coast wants to borrow it to format their own drive.
Ebay seems to have cheap ones every so often just under "zilog Z8" but they've all been the 6803's.
Anyways, I can hold onto the chip regardless should for some random reason I come across a 5mb Profile or someone out on this coast wants to borrow it to format their own drive.
Ebay seems to have cheap ones every so often just under "zilog Z8" but they've all been the 6803's.
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