[Coco] OS9 help needed.

Walter zambotti at iinet.net.au
Mon Dec 24 21:42:33 EST 2018

Sorry my response is not inline but my mail client doesn't support that option.

Thanks Curtis

I was concerned that the moment I modpatch'd the in mem D0 descriptor it would not like accessing the 35t_ss floppy it had
booted from.

But it definitely worked!!!  :)

Thanks Tfaden

I like the drivewire solution but how would I get the drivewire drivers/descriptors onto my OS9 boot floppy in the first place?

(Answer. I'll order the mini Flash with HDBDOS preinstalled from Cloud-9.  Yes, No ?)


-----Original Message-----
From: Coco [mailto:coco-bounces at maltedmedia.com] On Behalf Of L. Curtis Boyle
Sent: Monday, 24 December 2018 1:05 AM
To: CoCoList for Color Computer Enthusiasts
Subject: Re: [Coco] OS9 help needed.

There is a temporary way to patch d0 after you boot, using MODPATCH (which is included with OS-9 Level II). You can use this to change d0 “on the fly” to 40 track double sided, and then you make a new boot disk with that modified descriptor in memory.

So, in your case:
1) Boot your original Lvl 2 floppies
2) Type MODPATCH (warning - it doesn’t have prompts)
3) Type L D0 (link to D0 module). If successful, it will print D0 on the screen.
4) Type C 18 23 28 (This changes # of tracks from $23 to $28 - 35 to 40 in decimal)
5) Type C 19 1 2 (This changes # of sides from 1 to 2)
6) Type V (re-verify the CRC on the module)
7) Hit SHIFT-BREAK (ESC) to exit modpatch.

At this point, you should be able to access the drive as 40 track double sided, until  you reboot. You can also COBBLER a new disk which will have the new 40 track, double sided D0.

L. Curtis Boyle
curtisboyle at sasktel.net

TRS-80 Color Computer Games website

> On Dec 23, 2018, at 6:32 AM, Walter <zambotti at iinet.net.au> wrote:
> Hi
> I found my original OS9 Lvl 2 floppies.
> Can someone remind me how I can access a 40 track double sided floppy if the
> boot floppy
> is 35 track single sided?
> I tried loading the d40_ds.dd from the modules directory but of course it
> can't overwrite the
> /d0 module that is already in memory.

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