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The Official Nabu PC Floppy Disk Controller thread

C128 Guy said:
This is the generic response he sent out to everyone:
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I did buy one from him and received it through eBay before all of the videos started and he got bombarded. He shipped it out next day but I can see how he's delayed now and how eBay reacted. Some eBay scams sell popular items for under market value and get a bunch of buyers all at once. He'll be fine once he sends the backlog out.
 
1985MR2 said:
@Klyball, I just saw Leo Binkowski’s YouTube video.
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I had seen this earlier. As I had suspected, the cards are daisychained via the previous card where the FDC is the first. My Nabu PC has -12v on that connector. I wonder if the serial cards or maybe the hard drive card used that voltage. The floppy disk controller does not.

I am also communicating with Leo to help him get his disks archived. I REALLY want to try one of his disk images and see if the one I have works for him where it doesn't for me.
 
snuci said:
I checked each of the 24 pins to confirm continuity on both sides when documenting the cable pinout. Pin 24 on the WD1797-02 is 1 Mhz.

I believe I made the disks correctly via the proper settings via ImageDisk and with the help of the "Bad Disk Image?" thread, I could verify them with 22Disk.

To be sure, I also made the disks with the actual Nabu disk drive. This is how I determined one of my drives is bad (B drive).

I appreciate the suggestions.
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@snuci Have you confirmed all the ram is good , 1 bad bit in one chip could be the culprit. it sound like it's starting to load
 
It is starting to load. And I've removed and socketted the RAM on my Dev Nabu and tested each chip. I will post a quick video once I figure out how to sync up the refresh rate with my camera (if it's possible).
 
I put up a portion of a video I am working on to show what happens when I try to boot CP/M from the floppy drive on my Nabu PC.
I will probably remove this video once I have the full video done.
 
@ snuci if you try and boot it with a blank disk does it give the error DISK DOES NOT CONTAIN A SYSTEM TRACK
 
I have tried to boot several disks. I will get that error and other errors. Sometimes, it will just restart depending on the CP/M version. At one point, I took a Nabu disk, removed all of the files and tried to boot, then removed the system track and tried to boot and at that point, I got that error. It's like it's reading the boot track and then dies when it gets to the data tracks. This is why I want to try alternate software.

EDIT: I just checked the firmware are I have gotten a "Load Error, Reset NPC" error as well. There are a couple of CP/Ms that use a similar disk format but the offset may be different. I think one of those gave me the "Load error". Might have also been when I removed all system files. It's checking and indicates errors properly. All three CP/M disk images for the Nabu PC show the same results as the video.
 
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That seems to indicate its reading the disk to a point , would be nice to see what it is doing while its just spinning its wheels. my hands are tied until i get a machine. and make a card.

i wonder if its waiting for some kind of response from ? adapter box ?
 
Interesting point. I could hook up the adapter box and see if that makes a difference. It looks like it's working to a point. I have some Saleae logic analyzer data in this directory: https://vintagecomputer.ca/files/Nabu/Logic_Analyzer_Sessions/ but being honest, I haven't been able to decipher it myself.

If the Nabu Network recreation project needs the floppy drive, I am guessing that will hopefully work because the adapter is being emulated? I am waiting for the opportunity to try that out.
 
snuci said:
I had seen this earlier. As I had suspected, the cards are daisychained via the previous card where the FDC is the first. My Nabu PC has -12v on that connector. I wonder if the serial cards or maybe the hard drive card used that voltage. The floppy disk controller does not.

I am also communicating with Leo to help him get his disks archived. I REALLY want to try one of his disk images and see if the one I have works for him where it doesn't for me.
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wow i just watched that video , i would be great to see it boot with some of that software. that's a lot of disks to archive super cool
 
snuci said:
Interesting point. I could hook up the adapter box and see if that makes a difference. It looks like it's working to a point. I have some Saleae logic analyzer data in this directory: https://vintagecomputer.ca/files/Nabu/Logic_Analyzer_Sessions/ but being honest, I haven't been able to decipher it myself.

If the Nabu Network recreation project needs the floppy drive, I am guessing that will hopefully work because the adapter is being emulated? I am waiting for the opportunity to try that out.
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Do you have a Gotek? The FlashFloppy firmware has a front-panel display option that can help you figure out what track it's dying on, and sometimes it's faster to stuff a USB stick full of "every permutation of geometry" disk images rather than keep writing disks. I made a 5.25" card edge to 34-pin "pin header" style adapter for another computer that I can plunk in the mail if you'd like to try that.
 
Wish I bought one of these. Looked past few days on eBay and all the machines are gone... They sold out fast!
 
Klyball said:
i was thinking of adding a 34 pin header on that card so a regular floppy cable could be used and the holes would be hidden if i wanted to use the centronics connector
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I think that would be a good idea. If there is room, perhaps extend the power in the appropriate connector so that you can power the floppy up from the board as well? This way, no external power supply is needed. That is, if there is room.
 
Klyball said:
i wonder if its waiting for some kind of response from ? adapter box ?
Click to expand...

I connected a Nabu adapter box to the Nabu PC and got a screen I was expecting...

Nabu_adapter_floppy_boot_screen (Large).JPG


but when it tried to boot, it would give me a "BOOT ERROR" and go back to the previous menu immediately.

Nabu_adapter_floppy_boot_error (Large).JPG

I would normally get this when I put in just any disk without a CP/M boot track!

This makes things interesting because I now have an error to work with but I have only one option with the disk image I have and that is to try, one last time, to make the Nabu CP/M boot disk with the original Nabu floppy drive just to make sure there are no head alignment issues. Failing this (and I think it will because I did this before), something may be preventing CP/M from booting and I wonder if there is some sort of "authorization" by the Nabu adapter box or something? Maybe serial numbers need to match with the diskette? I don't have the original adapter box that went with this Nabu PC I'll see if there is any firmware in the adapter box. Luckily Dave Dunfiled has a picture of his serial number, if that is even needed. He did have one. I just never got it.
 
I don't know if this would apply in your case but when working with .IMD images that I know should be good, when they are for low density controllers I force translation of 500k and 300k to 250k.
For some reason imagedisk will pick 500k to write.

Larry G
 
As a follow-up, I don't think there is any copy protection or anything related because I could not find the serial number anywhere on the disk image. When Leo Binkowski makes images of his disks (video link on previous page), I can try that. I will, however, keep trying different things.
 
snuci said:
I think that would be a good idea. If there is room, perhaps extend the power in the appropriate connector so that you can power the floppy up from the board as well? This way, no external power supply is needed. That is, if there is room.
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Yes, good plan. I don't want to stray to far from the original, but a few practical changes will be good, or might as well just redesign. When i did the OSI 600D i changed the keys to cherry instead of the old at the time unobtainable key switches.
 
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