Sanyo MBC555 RAM test

[Witchy]

Hi folks,

I have a pair of MBC555s which both work as expected (slowly ) until I add the apparently rare CGA+256K RAM card at which point they'll start booting then fail at the same point and just print "his hi hi" on screen. I'm using the official CGA boot floppy.

If I disable the RAM on the CGA card by removing a chip then all is OK. None of my disks have anything useful like a RAM checker so does anyone know if such a thing exists?

Ta!

 

[digress]

You need the special cga boot disk to use the cga graphics. you also need to then hook up a cga monitor to the 9 pin cga board or the composite colour out. I have the disk here as a disk image if you can expand and recreate the disk. I have the regular cga board without the extra 256kb ram

http://eriscreations.com/index.php/sanyo-mbc-550-vintage-computer-fan-site/sanyo-disk-images/

here are some screen shots of it running some cga programs

http://eriscreations.com/index.php/sanyo-mbc-550-555-running-cga-graphics-with-special-video-board/

Hi folks,

I have a pair of MBC555s which both work as expected (slowly ) until I add the apparently rare CGA+256K RAM card at which point they'll start booting then fail at the same point and just print "his hi hi" on screen. I'm using the official CGA boot floppy.

If I disable the RAM on the CGA card by removing a chip then all is OK. None of my disks have anything useful like a RAM checker so does anyone know if such a thing exists?

Ta!

 

[JohnElliott]

Or if you've got a DS-DOS boot floppy, you can run VIDEO.COM to switch from native to CGA video.