This is a discussion to share my experience with DOS/65 for OSI and building a new DOS/65 with modified BOOT.ASM and SIM.ASM, then running SYSGEN to create it.
First let me say that I have a Superboard II expanded with an S-100 Bus that contains a video card that I wanted to drive from DOS/65. See topic “Superboard Expanded on S-100 motherboard ” if you want toknow more. That’s when this adventure started, and after about a month of trial and a lot of error I finally succeeded. But those that have been assisting me had very experience with DOS/65. Here are notes on what I think I have learned in order to solicit comments from other users, and perhaps the author Richard Leary.
1) The included editor manual is not very clear how to edit an existing file, especially a large one like SIM.ASM. It discusses in depth how to delete and add/replace lines of text and find a string but what is missing is a clear example of how to do that. The answer is that after opening the file with EDIT.COM the user needs to execute an “nA” (APPEND) command to get part of the file into the text buffer and execute an “nW” (WRITE) command to write the (modified) buffer contents, and repeat the “nA’ and “nW” as necessary to edit any remaining text. Then the user must execute the “E” (EXIT) command when finished.
2) The System Interface Guide and the SYSGEN manual discuss some of the parameters that define the system you are building but I failed to understand how create a system when either BOOT.ASM or SIM.ASM is larger than what is included. I changed the “msize”, “pages”, and “systrk” parameters in both files but never succeeded in building a system that would boot.
3) I eventually realized that floppies with a custom system are not completely compatible with the standard DOS/65 set of floppies for COPY and MOVE to work properly so I decided to make my modifications without changing the length of SIM. And my modifications replace existing lines of code in SIM.ASM without destroying it’s function or size.
4) Responses to prompts when running SYSGEN must match the “msize” and “pages” parameters in BOOT.ASM and SIM.ASM. SYSGEN will abort with a “bad filename” message if they do not.
5) Some provided programs, such as MODEM.COM need to be modified to run on OSI but the author does not provide specific instructions. Has anyone improved or enhanced the set of apps that are included in the set of DOS/65 floppies?