Computerland BC88

[falter]

Picked up a Computerland BC88 with a Paradise Mono / Color card in it.

When it arrived it was set for Monochrome, I read the manual and changed the jumpers to CGA. Supposedly it can do 4 color CGA at 640x350.

The only RGB monitor I have at present is an IBM 5154. I assumed this would work... we used it with our CGA hobbled AT when I was a kid.. but it won't sync to it.. just get a black screen while the machine goes about its business.

Am I forgetting/missing something?

 

[VileR]

"CGA at 640x350" is a contradiction in terms. Unless it's some interlaced or double-scanned thing to increase apparent resolution, but that would be x400.

Sounds more likely that it refers to displaying CGA software on a monochrome monitor, at 4 brightness levels standing in for colors. A few of those odd early cards could do that. Might explain why the 5154 doesn't like it.

Any more identifying info on that card? Or just Paradise and Mono / Color?

 

[SomeGuy]

Is that a Paradise MGC II? Does it have any of the optional module boards? Yes, those things emulate CGA when connected to an MDA monitor. So that is not really the resolution you are using, but that is what it is sending the the monitor. When using an actual RGB or composite monitor, you don't really get anything other than standard CGA capability.

Crazy thing is in MDA mode it uses an expansion ROM to do some of its tricks. It runs without extra software, but there was supposedly a driver disk that improved compatibility with some programs. As far as I know that software has never been archived.

 

[Chuck(G)]

Ask Werner Erhard (very inside joke).

 

[falter]

Is that a Paradise MGC II? Does it have any of the optional module boards? Yes, those things emulate CGA when connected to an MDA monitor. So that is not really the resolution you are using, but that is what it is sending the the monitor. When using an actual RGB or composite monitor, you don't really get anything other than standard CGA capability.

Crazy thing is in MDA mode it uses an expansion ROM to do some of its tricks. It runs without extra software, but there was supposedly a driver disk that improved compatibility with some programs. As far as I know that software has never been archived.

I'm not sure.. only name I could find on it was 'Paradise Monochrome Color'. This is a close up of it:

https://drive.google.com/file/d/1teX_VBmIJDKsNi95FfRgSfqOpTBDRl4Y/view?usp=drivesdk

And yeah.. I'm not getting anything out of my 5154 while connected to it. No text or graphics. Just black.

Here's an ebay auction featuring the same card: https://www.ebay.com/itm/123989834685

 

[SomeGuy]

Hmm, that looks like a more common color/mono card that simply operates as one or the other depending on the jumper setting. Either way, the high x*y value is almost certainly just the resolution sent to the monitor in mono mode.

So if you are using an RGB monitor, make sure it is jumpered for color.

 

[falter]

Yeah it's definitely set up right.. or at least, it works great with my EGA machines. I actually don't have a straight up CGA adapter anywhere.. I should get one and see what happens.

 

[laputa]

I also have a BC88 (variant of Trigem 88II) and tested with various graphics cards. It always showed great compatibility. Unfortunately, I don't have proper Computerland MS-DOS with BC88 CPU speed control and RTC setting utilities, I always have to use it in 4.77mhz low speed status.

 

[JonnyGators]

My recently acquired BC88 has a different video card, it's a CGA and has the standard RGB connection you'd expect, and 2 RCA connections. Both the RCA connections work on the composite input of my TV, one seems to be black and white, the other color. I don't know much about the history of this machine I just acquired, so I don't know if this video card is stock. I can't find any identifying information on the card, just a label that says EP 302729, which doesn't help me much on google.

I don't remember what the back of the video card looked like in our BC88 family computer, so I'm not sure what that came with.