5.25" 10 sector hard sector floppy disks no longer available

[mnc1959]

Doh!

Doh!

Martin,

Your disassembler probably needs a binary file, not an ASCII hex file. The bytes shown in the disassembly listing are:

33 45 46 46 44 33 30 33 0D 0A

Which is the character string:

"3EFF303" followed by a CR and LF.

Mike

Duh! Oh yeah, its been a while since i played at this level, thanks for pointing out my obvious mistake.

Cheers, Martin...

 

[mnc1959]

Duh! Oh yeah, its been a while since i played at this level, thanks for pointing out my obvious mistake.

Cheers, Martin...

Quick update, found a great utility, hex2bin, converted it to a .HEX file, exactly 2048 bytes long and was able to start disassembly.

Yay!

dZ80 also identifies any IO poprts being used, so i already have a quick map of the IO port addresses on the board, just have to work out what device is at what address

More investigation coming up.

Cheers, Martin....

 

[mnc1959]

Mike,

Another quick update.

The floppy drives are shipping monday/tuesday next week and should be here by the weekend.
The Serial IO board should ship around the same dates but from USA, I envisage that taking 2-3 weeks to arrive.

That means I know the serial IO board is a Wamenco IOB-1 board with a 8251A Uart.

If I am understanding correctly, all that needs to be done is to tweak the BIOS for the Micropolis drive and add in the 8251A code and it should be pretty simple to create a bootable disk?

Hmm, I have 2 boxes of floppies in USA, Should I have 1 redirected to you to put the Micropolis images on?

Would we start with a basic CP/M system ie with maybe support for 32K?

I have not had to build/have built CP/M like this before.

The 8251A along with the 8255A use 6 out of 8 IO addresses, I can set the address to anyone of 32 starting locations. I need to check it does clash with the Micropolis FDC board, hmm, the Micropolis controller seems to be memory mapped, using 1K, I guess it makes sense to place it as high as possible, Im pretty sure the ZPU board can be configured to jump to the boot ROM on the Micropolis FDC. Im not sure if the Micropolis FDC needs to sit at the top of ram or there can be a gap between the top of ram and the boot ROM address. Ideally Id like to bring the system up with say 32K or 48k of ram and then I can work towards increasing ram up to 56K or more hopefully.

I just checked and the ZPU can be forced to jump to address F000h, I can configure the Micropolis FDC to have its boot address at F000h, a bit wasteful of the top 4K address space, but that should allow for a CP/M system of up to 60K. One of the memory boards can have a ROM at F800h so I might look at a 2K monitor ROM like Zapple and relocate the code to F800h. Hopefully I can 'adjust' the addressing on the ZPU to jump to that address, ideally configurable via a switch to allow boot to CP/M or boot to monitor.
In the short term I will rely on the system booting from the Micropolis board and the CP/M image I get from you.

Are there any monitor roms you can point me at other than Zapple?

Any hints/tips/suggestions are appreciated, given you are helping me out I will do whatever you suggest to minimise your effort.

Cheers, Martin...

 

[mnc1959]

Martin,

If you buy a Vector-Graphic ZCB (CPU), it has a built-in serial port and a ROM monitor for which I have a utility that can write Micropolis disk images transferred via the serial port from a PC - you could write the boot disk yourself!

Frankly, I could probably modify the utility to work with whatever CPU and serial port configuration you end up with if you'd rather write the boot disk yourself. I could create the disk image file for your machine and you could then use the utility to write the disk image to a floppy.

Mike

I like the prospect of writing the disk image myself as it gives me a backup. I haven't seen a Vector-Graphic ZCB (CPU) available so Im stuck with what I have. The RASE80 board has a monitor and space for other ROMS, the ZPU board has no space for a monitor ROM, but I have a TANNER 64K SRAM board that takes 32 x 6116 SRAM with the option of the top 8 devices being replaceable with 2716 EPROMS. Meaning I can put a monitor ROM on the board easily. Where do I start with creating a monitor ROM for my hardware configuration?

Cheers, Martin...

 

[smp]

As the OP, I would like to pose the original question again:

Does anyone have a source of supply for 5.25 inch 10 sector hard sector floppy disks?

Thanks,
smp

 

[billdeg]

no. I split a case of boxes with a fried about 5 years ago last time I saw any for sale, but I would think they're out there if you keep checking Ebay.

 

[smp]

no. I split a case of boxes with a fried about 5 years ago last time I saw any for sale, but I would think they're out there if you keep checking Ebay.

Thanks very much for your response, Bill. That gives me a good data point. There's a fellow here on the forums who indicates he has a large stash of them from a situation where data was recored once and then read once, but they are marked with some classification markings, so he doesn't know if he can share them. Bah!

I'll just have to keep looking.

smp

 

[griffk]

Thanks very much for your response, Bill. That gives me a good data point. There's a fellow here on the forums who indicates he has a large stash of them from a situation where data was recored once and then read once, but they are marked with some classification markings, so he doesn't know if he can share them. Bah!

I'll just have to keep looking.

smp

Just an FYI to all on the N* diskettes...

I contacted security @ Ames.NASA and made a formal request for a determination on these guys---probably shouldn't have been so ANAL about it in the first place, but I should have an answer in a week or so (probably a little longer with July 4 coming up)

gwk

 

[mnc1959]

Martin,


Frankly, I could probably modify the utility to work with whatever CPU and serial port configuration you end up with if you'd rather write the boot disk yourself. I could create the disk image file for your machine and you could then use the utility to write the disk image to a floppy.

Mike

You have me intrigued, I was going to ask if you could copy some sort of serial file transfer utility so i can change/build/adjust disk images myself. It sounds like you have already written such a utility?

Once I have a bootable CP/M disk and your transfer utility I should be able to tweak and adjust to my hearts content.

I would appreciate both CP/M 2.x and MDOS if not too much work.

As per my previous post it's all on its way and its a matter of waiting, although i'll do some configuration of the ZPU board and RAM boards in anticipation of the Micropolis FDC and the Wamenco IOB-1 boards.

Cheers, Martin...

 

[deramp5113]

Martin,

I'll be glad to help you get up and running with the Micropolis drives. We've kind-of hijacked this thread though -- lets start a new thread, or PM me and we can exchange emails and proceed from there.

Mike

 

[mnc1959]

Martin,

I'll be glad to help you get up and running with the Micropolis drives. We've kind-of hijacked this thread though -- lets start a new thread, or PM me and we can exchange emails and proceed from there.

Mike

Hi Mike,

Yes, I agree, my apologies to those who originally asked about 10 sector hard sectored diskettes.
I have started a new thread, entitled "Rebirth of an S100 System".

Cheers, Martin...