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Hi Everyone. When I purchased my C4P/MF, it didn't work. (You can read my other thread on how I got it working etc.) Once got it working, I was rather upset that BASIC didn't spring to life when I turned it on. My previous experience was with a Superboard II and a C1P (essentially the same machine) ...

Oh wow. I had almost the same issue this morning. While typing in the monitor characters and graphics were spewing all over the screen. I figured it was ram and probably page zero because it only happened when keys were pressed. Which meant the vectors stored in zero page were likely wandering. I re...

Here is the disassembly so far... ; Jeff Ferguson, Chaos Designs ; Created: 2014-05-30 18:33:48 ; SYN600 Notes: ; The 3 of the 8 256 byte pages in this rom are mapped into 3 areas ; of the computers, $FD00, $FE00, and $FF00. Different pages are ; used depending on the system. (Tape based, Disk based...

Yes. I have the disassembly. I hadn't thought that the images would be different for 5 and 8, but of course they are!!! I will stick with 5 right now. I have mostly finished my disassembly of the boot rom. The boot process starts in the rom, then to track zero and one and then onward from there. Wha...

I want one so bad, I can taste it!!! I am currently working on dissembling the SYN600 ROM and noticed that, on the C4P, anyways, storing anything other than $00 in memory location $FB (zero page) transfers input from the keyboard to the ACIA at $FC00. Clearing $FB back to zero restores native keyboa...

Thanks, Phil. I am evaluating them now.

Oh, and I just performed the 1200 to 9600 baud upgrade on my C4P/MF. It was pretty simple.

Regards
/Jeff

Hi Guys, I am going to document the startup process. Can any of you tell me which version of the Operating System that the C4P/MF uses? I have seen versions for the C1P the C4P and the OS-65D and OS-65P and versions 3.0, 3.1, 3.2, and 3.3. Which would be the best target to investigate, and where wou...

I notice, as you did that each byte written has no more than 1 bit set. I'm thinking timing.... maybe the "thing" that does the writing isn't waiting for all 8 bits before it writes. Do you have a schematic?

As it turned out, it was one of the 8T26's that buffer the keyboard inputs on the video board. I had concluded that it was not anything on the 542 keyboard board because both worked in the C4P. During the process one of the video RAMS died, so I had to replace it also. On to the serial connections a...

THAT is a VERY HAPPY screen shot!

/Jeff