1 Feb
2003
1 Feb
'03
4:29 a.m.
Ethan wrote:
If I were more comfortable with FPGA/CPLD design, I
would probably go
that route. My expertise is more in microprocessors; I was contemplating
throwing an MC68000 on the other end of the bus..........................
I was thinking of recycling the COMBOARD design - 1/4 of the memory
map is "shared memory" - there is a circuit between the 68000 and
the host bus that initiates DMA cycles when the 68000 reads/writes
to it. I have used a COMBOARD to test the RAM in a PDP-11/03 via
this shared memory interface.
I got a 4 Mpixel camera for Christmas that came
with a 16 Mbyte Compact Flash Card. After Christmas
I picked up a 64 Mbyte CFC to use with the camera
just so I would have the storage for about 50 pictures
instead of just 12. I also picked up a Dazzle USB
Compact Flash Card Reader/Writer for $20 for my
sneaker net needs. So now when I'm around computers
I carry the CFC reader and the CD with the USB drivers
and I basically have a removable hard drive that I
can carry in my pocket.
So now I'm thinking about how hard it would be to
create a cartridge for say - the C64 that has a USB
port and an EPROM on it. The EPROM would have routines
that wedge into the Kernal disk routines on boot. (And
of course they would bypassing the serial routines) Plus
routines to translate disk commands to read and write
files.
Imagine a hot swapable 512 MB hard drive on the
C64 with an access time of RAM.
Regards,
--Doug
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Doug Coward
@ home in Poulsbo, WA
Analog Computer Online Museum and History Center
http://dcoward.best.vwh.net/analog
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