[Coco] DOS patch programs

Christian Lesage hyperfrog at gmail.com
Sat Apr 4 15:04:32 EDT 2009


Roger Taylor wrote:
>
> Also, CoCo 3 users trying to patch their Disk BASIC ROM while it's in 
> RAM and saving out the image to burn to an EPROM should know that the 
> ROM won't run right on a CoCo 1 or 2.  The correct way to patch the 
> Disk BASIC "2.1" ROM is to run an All-RAM routine first that recopies 
> the original BASIC, ECB, and Disk BASIC ROMs into RAM, perform the 
> patches, then save the images.  Depending on the situation and the 
> ROMs in use, this might not work sometimes....
>
> A cure I came up with is a new feature in CCASM that lets you write 
> DOS patch programs that are merged with an existing ROM image file to 
> create a ready-to-burn ROM.  For example, a typical CoCo 3 DOS patcher 
> is a LOADM'able file with multiple ORG statements that jump around the 
> DOS ROM/RAM making changes.  CCASM assembles the LOADM file then 
> overlays it with a copy of Disk BASIC 1.1.  The resulting ROM is 
> naturally compatible with all CoCos that can use a disk controller.

That's an interesting feature, but how do you do that? Using the 
"includebin" directive?

Christian



More information about the Coco mailing list