knudsen@ihwpt.UUCP (04/15/87)
In honor of all the Canadians who've been posting to this
newsgroup the past week (and even if they hadn't, 'cause this
gadget is pretty neat), I'd like to describe a new Coco
peripheral I saw at the Chicago RainbowFest this past weekend.
(It's made at the other end of the country from DISTO's Quebec,
namely in BC by Sardis Technology).
It's a floppy controller that avoids the infamous NMI-HALT loop
that deadens your Coco to the world whenever disk data is being
transferred. It substitues a simple polling loop.
An 8K byte Toshiba static RAM (you can plug in a 32K RAM!)
serves as a FIFO buffer to keep data from being lost,
AND to decouple/free/liberate your Coco from the disk action
itself. To write a sector (or more?) your Coco driver just blows
the data into the FIFO, and when it's all there the disk controller
chip is told to do the write.
Since the polling data-transfer loop has no critical timing in it,
it can be low priority, the interrupts are left enabled
(especially your keyboard!) and the Coco never freezes up.
Coupled with OS9 Level II windows, this little pack makes for
SERIOUS multi-tasking. Introductory cost at the RainbowFest
was $120 US, tho official price will be US $150.
All they had was a nice photo of a prototype; the assembly line
was just now starting to roll.
OS9 drivers will be included -- a version of DP Johnson's SDisk
for either Level 1 or II. BTW, its "power up" initial mode
is the old halt-on-NMI, so it's compatible with BASIC and old
OS9 drivers. Sardis Technology claims to have been making
industrial 6800/6809 boards for some years.
--
Mike J Knudsen ...ihnp4!ihwpt!knudsen Bell Labs(AT&T)
Delphi: RAGTIMER CIS: <memory failure, too many digits>
" ~E(x):[is_lunch(x) && cost(x)==0] "