forum.defence-force.org

Hi.

Here is some more of the BD500 history.
This was written by Jeremy P. Hibbins, who ran the Byte Drive Users Group
The price list I received from ITL Kathmill. Notice that it includes prices for a BD500 for the beep. As far as I know, this was newer released.

Ray030471 wrote: ↑Tue Feb 16, 2021 9:01 pm...

@Ray030471: Hello, Ray! Any updates on BDDOS

I've been doing other things for a while but I have made some progress on BDDOS. I have produced a new version of BD Basic and DOS. This new DOS allows for disk directories and includes instructions such as MKDIR, CHDIR & RMDIR. I am testing this but if there is enough interest then I will make a suitable ".DSK" and (mini) manual available via this site.

Everything is of big interest, even just short message with status update from time to time .

I am still working on this, currently trying to include fields in random access file records. It is often a case of 2 steps forward and 1 step backwards when trying to squeeze code and buffers into 2 x 16k.

Good to hear the project is still alive.
Keep us informed !

I need to find time to get my BD up and running.

I am making good progress with the BD500 operating system. Fields in random access files seem to operate well.
I am now working on FORMAT. However, I am having a little difficulty in understanding how the emulator handles the fundamental FDD commands to "RESTORE" to track 0 when the next access is to side 1 (as opposed to side 0), and "STEP IN" (both sides of the disk). Any help here would be much appreciated.
In the emulator, formatting generates 80-track, double-sided disks (the maximum size?) and the BD500 DOS manages smaller sizes. With the actual hardware, FORMAT will follow the drive specification.
Once I get FORMAT done, I will include COPY (file by file) and BACKUP (track by track for the whole disk). BACKUP on the emulator will present similar "RESTORE" and "STEP IN" challenges.

Sounds good.
Do you know anyone with info on the cable/ interface? I know someone over on Facebook that has BD but no cable. At least one of mine is faulty.
If anyone had circuit diagram we might be able to recreate one.

I believe Jeremy at the BDUG had problems building hybrids. I don't know what happened to what stock he had. As far as I can gather he has passed away so I'm not sure if we have any chance acquire any info or old stock. Peter Halford may be the only other lead - I'm not sure what happened to him? I'm not sure if you only worked on the software(?)

Ray030471 wrote: ↑Fri Mar 25, 2022 3:40 pmI am making good progress with the BD500 operating system.

Amazing! I can't wait to test anything related to BD-DOS .
About the emulator: don't use it as reference, there is no guarantee that it behaves as real hardware.
If you need something to be changed for test or any other purpose I'll do it asap.

I only worked on the software but if anyone has a spare Cumana disk interface then I believe that I could modify it to BD500 specifications. I don't want to modify my own Cumana disk interface just in case I couldn't revert to standard.

Not that long ago, somebody was selling Cumana disk controllers, can't remember whom :-/

I have the Cumana interface circuit boards (from Steve Hopps).
Just need to solder them together!
I 've got most of the components but work on soldering has stalled due to lack of time. And I'm not that great at electronics.

I could do one of those boards. I have a FDC1793 chip (probably ok) and some of the others required but a little help here also would be appreciated.

Cumana used the 8877 chips - I have lots of them. There's a sight difference. A couple of external components required, I think.

I've had a closer look at my FDC board and realised that there are two different circuit designs. It appears that I have one which was produced by the "ORIC RESEARCH CENTRE". I hadn't realised that there was much of a difference until now - thanks for alerting me to this.