[Coco] Making my 80T 2S OS-9 Boot Disks boot able

Stephen Fischer SFischer1 at Mindspring.com
Tue Mar 27 13:42:23 EDT 2018


All my disks are 80T 2S DNS=3 as I had both 5-1/4" 80T 2S drives and 
then added a 3.5" 80T 2S drive. I could swap "/D0" and "/D1" with a 
switch, as long as the disks were stopped. I had identical copies in 
5-1/4" and 3.5" format. The DNS=3 is the proper value but most people 
used DNS=1 and got away with it as they did not read and write 5-1/4" 
40T and 35T floppies on a 80T drive. That is built into the drive 
software and has been since SDISK3 forced the main driver to do so also.

When I had a running NitrOS-9 system I could set the 80T 2S DNS=3 in the 
descriptor using DMode and I never had a problem reading ANY of my disks.

I know how to do all that you said but I do wonder if it is necessary.

As I have no problems reading my 80T 2S disks being able to boot one in 
my mind is just the location of the boot track being incorrect. I had to 
run a program in the early days to correct the location of the boot 
track as I had 2S disks. That might need to be reversed.

Can you extract the boot track from my original disk?

SHF61 is listed as a single sided OS-9 L-I Boot Disk.

That may work as is.

My OS-9 Disk Index:

http://cococoding.com/sfischer/SHF%20OS-9%20Disks/Indexes/SHF001.pdf

My weather station just died and I want to swap in another laptop 
quickly. Hopefully I will get a good USB to serial adapter and not one 
of the bad ones.

So, when the MB is replaced in my Backup HTPC I will have zero (0) 
computers with a floppy drive unless I put the failing MB in another 
case, but then I would have no monitor for it.

Thanks for your help. I am giving up trying to ready my old e-mail from 
the failed W7 computer using Vista on Hyper-V. The files will not transfer.

So I should be able to getting a running VCC system on Vista hosted by 
Hyper-V on my new W10 laptop soon.

SHF

On 3/27/2018 7:12 AM, Robert Gault wrote:
> Stephen Fischer wrote:
>> I just realized that the floppy controller in SHF15 was for the DISTO 
>> No-Halt and that may be why it
>> may not boot.
>>
>> I keep thinking that the offset to the boot track is messed up by the 
>> conversion to a .dsk is the
>> problem. That's why I asked the question for using DED. Double sided 
>> disk to single sided .dsk.
>>
>> So I must either find what I did for the original Jeff Vavasour's CoCo 
>> 3 emulator, Or try another
>> disk. Someone wants to stay far far away from NitrOS-9 Level-I due to 
>> the decreased memory available.
>>
>> So it's OS-9 Level-I that needs to be booted in VCC, I just thought it 
>> was better to go with my last
>> system which I want to get running anyway.
>>
>> Perhaps SHF13 OS-9 L-I V02.00.00 which may use SDISK.
>>
>> <snip>
> 
> OK! Just looked at the .dsk image you posted and have made progress.
> 1) As is, the .dsk can't be read in either VCC nor MESS but can be read 
> if mounted in Drivewire.
> 2) Seems the DD.FMT byte on LSN0 is not liked by current emulators.
> 3) I changed DD.FMT from $07 to $03 using my Basic COLORZAP program as 
> DED would not access the disk.
> 
> Now I could read the SHF15.dsk image when mounted in VCC or MESS while 
> running NitrOS-9. I could also BACKUP the disk under OS-9 to an 80 track 
> double sided disk image via VCC or MESS.
> So, what you need to do is:
> 1) Alter byte $10 on your SHF15.dsk image to $03 from $07 with a PC 
> program if necessary.
> 2) Create and format (NitrOS-9) a new disk with cyl=50 sid=2.
> 3) Use a NitrOS-9 script for OS-9 Level 1 V2 to os9gen a standard 
> bootable disk created in step 2.
> 4) Backup the SHF15.dsk to the new boot disk which should give you 
> everything except T34 and OS9Boot on your SHF15.dsk.
> 
> With luck, the new disk should boot from VCC or MESS and work as 
> desired. If not, you may need to separate all of the modules in the 
> original OS9Boot file and replace CC3Disk with a standard one. Merge all 
> the files back into a new OS9Boot file and copy that to the disk created 
> in step 3) above. Alter LSN0 to point to the new OS9Boot, and do a Backup.
> 
> Confused! :) Well just send me private email and we can go over it step 
> by step. Or I can just try to create a bootable copy myself and email it 
> to you.
> 
> Robert
> 
> 
> 
> 


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