[Coco] Emulator

Robert Gault robert.gault at worldnet.att.net
Mon Sep 7 16:52:01 EDT 2009

Wayne Campbell wrote:
> I just woke, so I'm not quite in the code-mode yet. However, I've been
 > thinking alot about this. As I've said in other posts, I can't be sure if
> what I'm seeing is "normal", or if it is something being miscalculated in
> the emulator (first step), something miscalculated by NitrOS-9 (second
> step), or if it's Basic09 (third step). I know that mfree from the command
> line shows me memory allocations all the way up to 512K (the ram setting
> in the emulator for the 6809 CoCo3 roms I have). As I recall, the original
> OS-9 Level II displayed memory allocations up to the 64K limit. Everything
> above that was in a separate line, as a single block.

The current version of NitrOS-9 will recognize memory up to 2Meg. It 
will not indicate more memory even if it is present in MESS or a real Coco.

> Basic09 had approximately 40K of workspace in the original version under
> Level II. Once you got to about 36-38K, you would start to encounter
> 43 errors (unknown procedure) when running external machine language
> subroutines, like Inkey or SysCall. If I open the Basic09 I'm using under
 > NitrOS-9 with over 23K, nothing runs and I get constant 43 errors.

There are two ways to start Basic09 with more than the default amount of 
memory. You can use the MEM command from Basic09 which is limited to 32K 
or you can start Basic09 by "basic09 #nmk" where nm can be up to 40.
I just entered "basic09 #40k" and MEM responded with 40959.

I don't get errors when using Basic09 with the above amount of memory.

> Wayne

More information about the Coco mailing list