OS65D3.3 Mods for 2K Display

[bartleph]

Hello again,
I have my SBC and floppy disk interface hooked up and working really well. I can load a slightly modified version of OS65D3.1 and OS65D3.3 from my Gotek Floppies. I have now built a Display board to add to the system which has 2k of memory from $D000 to $D7FF inc. All characters can be seen on my monitor and writing directly to screen addresses works perfectly. I would like to be able to modify the Disk OS so it uses this extended screen. Does anyone have the details of a relevant patch to do this?

Just didn't want to re-invent the wheel if someone has already done it!!
TIA.

[wawa.voun]

Hi,

Give a look here : https://download.system-cfg.com/f.php?h=1HCvnY01&d=1

This is also on the web in english, ask google.

I think Elektor has do the job for you.

I own a Junior with VDU board (6845 + 2kb video memory) and OS65D patched like indicated in this article work like a charm.

But I think you need a program to manage the display (carriage return, linefeed, escape codes etc...). OS65D cant do that.
The patch basically indicate another address that serial port for char output. At this address you need this program for managing the screen.

On the Junior this is done by code in eprom called PMV (Printed Monitor Video). If you need sources ask.

Regards.
Philippe

[bxdanny]

bartleph,

While I don't want to belabor the obvious, have you tried sim[ply sending output to device #2? That is, do something like

PRINT #2, "Some text"

You could also say LIST#2 to send a whole program listing to the #2 device, which is normally the video display. Depending on what version of the operating system your disk was modified from, this may or may not work correctly. Maybe it won't work at all if the video driver that was there has been overwritten with something else, but it is certainly worth trying if you haven't already.

[bartleph]

Thank you both for your replies.
I'll keep the forum posted on how I get on..

Paul