OSI 502 CPU Build Questions

[nbreeden2]

Hi all, I'm new to the forum.

I'm currently building a 502 CPU board and 480 backplane as part of a bigger project. For now I hope to get the 502 board running using serial I/O and supporting BASIC. I'm configuring the CPU to use 2716 EPROMs and have a stock of 2716s and programmer. I also have a good stock of 2114s so I will be using the on-board RAM.

Which ROM images downloads should I use? I'm guessing:
SYNMON1 for the Monitor?
BASIC-ROMS for BASIC?

Assuming SYNMON1 is what I need how does it configure the 6850 ACIA?
Divide by 16 for BAUD rate?
8N2 for the serial settings?

I'm curious if anyone has disassembled the ROMs? If so where can I find the files?

-Neil

[Getagrip]

Synmon1 for the monitor is correct. The 6850 ACIA should be located at $fc00-fc01. The serial port on my 502 board is configured for the cassette interface at 300 baud. I believe the ACIA is set for divide by 16 for the baud rate.

Look for the roms at https://www.osiweb.org/software.html - There is an assembly listing there which is pretty easy to follow.

My 502 gets it's clock from the 540 video card, so you may need to implement a cpu clock if you do not have the video card. I have not successfully got the system to boot directly to serial mode with the video card installed so there may need to be some configuration there.

Good luck!

Mike

[bxdanny]

Actually, the assembly listing for the SYNMON1 ROM (and others) can be found at http://marks-lab.com/osi/software/roms.html.

The link that getagrip gave unfortunately contains only the binary contents of the ROM (in raw 8-bit form and as a text file of just .byte directives). Other than that, his information is good.

=Danny

[Getagrip]

bxdanny is totally correct. I saw the zip file with the same name and did not check the contents. My bad.