OSI BASIC Question

[Mark]

The OSI screen clear is managed by the boot ROM. I don't think the 65A monitor and serial BASIC support ROM do that, so without that the screen can initialize in all kinds of crazy states depending on the memory chips involved.

There is an OSI configuration for 440 video with ASCII keyboard that could probably be tweaked for OSI540 & serial keyboard.

As for a monitor program, as a quick experiment I set up your configuration in WinOSI and loaded the OSI Extended Monitor program.
Overall it seems to work pretty well on a serial system although the Save and Load command don't work with a serial console.

I dumped the binary and wrapped it in a 65A load format using OSIALOD
Send this data to the OSI after entering the monitor with your terminal program using RAW send at 8N2 if possible.
The ExMon program loads from $0800 to $0FFF, It starts at $0800.
If the program doesn't start or malfunctions, you can Reset the OSI, Press 'M' and then 'G' to start.
To fix the 'G' starting location in 65A, enter the monitor and type L012C 04 FD 08 00 RG

With the Extended Monitor you can View/Modify/Transfer memory location, disassemble code, set breakpoints etc.

So you could fill memory with a value
FD000,D7FF=FF

then display those values (or watch your display)
DD000,D7FF

manipulate a specific address
@DE00/00 01
etc.

Of course you can manipulate memory locations with the default 65A monitor using Lxxxx aa bb cc dd ee ff to write memory where xxxx is the target address and aa bb cc dd ee ff are hex pairs (all uppercase). Press 'R' to exit L mode. Use Pxxxx to dump memory at the specified address, press any key to stop.
Try LD088 20 48 49 20 6C 6F 20 0B 0C 20 R

Good Luck!

[musovern]

Hi Mark,
Thank you so much the ExMon loaded fine over the serial port and started right up to the : prompt.
What a very nice Monitor and tools kit will come in very handy once I understand it a bit better.

I first tried the
FD000,D7FF=FF I presume this would fill the video memory and the screen the FF character(code) then I did a FD000,D7FF=30 and at least the screen is is displaying some sort of output. Now begins the fun part of working out what I did wrong in the build.

This is my setup for this build so far.



Boards are the Replica 502 ,OSI 495 prototype board with 32k RAM with 4K enabled plus the 540B video board.

Seems that BASIC is working fine over the serial port


Video board problem



So making good progress so far thanks to your ExMon.

cheers

Vernon

[musovern]

Hi Mark,

An up date got it all working now thanks so much. It took me awhile but had to re solder a few IC's sockets to get it working. It seemed to be on 74LS123 & 74LS92 then it came to like.

[Mark]

Good Job!
Glad to see it's working!

[dave]

That keyboard enclosure is just beautiful.