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Klyball, It sounds like you do have properly formatted tracks, otherwise I don't think it would have gotten as far as it did. Anyway, the first of the two options you listed is the right one - the gap comes after the first three bytes. But 9 tracks should be enough to boot the system (1-6: system co...

Klyball, Hi. What happens when you try to boot the disk that you created? Can you tell how many tracks are being read? The track 0 format is the usual one, the same as in 65D. In fact, you should be able to write it with the 65D Track 0 R/W utility (13 or "D" pages). I would think that any bytes pri...

Klyball, The 00s are important, don't leave them out! Use the "Clean" version that Mike posted, not my original post that had extra FF bytes on a few tracks. But you also need to leave a GAP between the header (first three bytes) and the rest of the track, about 300 microseconds I think. I studied t...

The same code is used for the $FFxx page on both serial and video systems. It fills $D000-$D7FF with $20 in order to "clear the video screen". It even writes the "H/D/M?" prompt into RAM at $D0C6. On a serial system (identified by having $FE01=$00, the second byte of the 65A serial monitor code), ea...

May I suggest you check your system and directory tk headers: 43 57 TK NB 58 76 01 08 The noise bytes certainly wouldn't be between the track number and the 58 (hex) "track type" code. If present, they would be between the 58 (last byte of the track header) and the 76 (first byte of the sector head...

When OSI sold the C1P Series II systems, using the 600 Rev. D board, they had the same SYN600 ROM that the earlier C1P systems had, which means there was no support of any kind in ROM for 48-character mode, or for writing to the port (at $D800) that controlled which mode the system was in. You shoul...

If I recall correctly, 48 char mode will survive a reset, but not a cold start.

No, that doesn't sound right. The ROM was the same as on the 600B, so there is nothing in the code that would change the screen mode.

A quick question for anyone with working 600D: If the board is in 48-character mode, and you press the reset button/Break key, does it switch back to 24-character mode? I seem to remember that it does, but I'm not sure.

The idea is intriguing, but I wonder how practical it is, considering that it would need additional address space for the ROM that is not readily available, at least not without introducing significant incompatibilities between the modified and unmodified systems. Maybe a CBM-style editor could be d...

Thanks, Mike52. I mainly had two questions about WEMON, namely whether it supported booting from an OSI-type disk (the answer is no, at least not without an additional ROM at $9800), and whether it was basically a clone of CEGMON (the answer is definitely not, so I guess Tom Graves, one of the CEGMO...