On Thu, Jun 24, 1999 at 02:57:12PM -0500, Andrew Davie wrote:
> "Microsha"
>
> Appears to be a (souped-up) Spectrum clone in functionality, but looks
> totally different. Quite cool, actually... Keyboard unit in dirty yellow
> (Atari 800-style colour and basic appearance) but much flatter (about 1.5"
> thick). Red and blue keys in a really weird cyrillic layout.
This machine has nothing to do with Spectrum; it's actually a "productized"
version of Radio-86RK a.k.a. RK86 (a machine designed by hams, its design
was published in "Radio" magazine in 1986 -- hence the name), with
different memory map and ROM entry points. It uses cloned i8080 chipset.
Its display is not bitmapped (display controller is a i8275), but character
generator contains block graphics characters, and BASIC interpreters use
them to provide 128x50 pseudo-graphics mode.
> What a bizarre organization!!!
Yeah ;) It took me a while to get used to QWERTY keyboard after using this
one.
> Unit has an expansion interface at back (RAM?) which plugs in at right
> angles (ie: a bit like a cart slot on an Atari 800, again). Several other
> interface ports on back, the most interesting is a square unit simply
> marked (interface 2) with a 3 x 10 female connector.
The expansion interface was meant for RAM or ROM modules or memory-mapped
devices. These were industrially produced -- e.g. ROM module with BASIC
interpreter, text editor and assembler.
Interface 2 is a generic parallel interface -- it is wired to an i8255.
There is no serial port.
> I have the manuals and power supply for this machine. I'll do a picture if there's any interest.
> I also have about ten cassette tapes of original software for this one.
There's an emulator of RK86 "series" of computers (RK86 itself, Mikrosha,
Apogei and Krista) at <URL:
http://www.uic.nnov.ru/~pyva/>.
I can type in some technical info (memory map, pinouts, ROM entry points...)
if you're interested.
--
Sergey Svishchev -- svs{at}ropnet{dot}ru
Received on Sat Jun 26 1999 - 13:18:24 BST