Prev: Replacement PLA-Eprom.
Next: Emulator - Bad lines and characters
From: Chris Baird on 1 Feb 2010 16:13
I've recently built a "$5" IDE harddrive interface for a
Synertek SYM-1 (see <http://www.twitpic.com/photos/Sym_Biosys>),
and now the idea is to bung one onto my C128.
For that, I'll need 16 bits of I/O...

I'm thinking this idea of using a 74LS373 would be the way to go:
<http://www.compeng.dit.ie/staff/tscarff/Parallel_Port/SPP_interface.JPG>
(Where this PC Printer Port expander uses STROBE, I'd be using
the User Port's PA2, probably into a 74LS139.)

Are there any examples (online) of this being done before for the
Commodore User Port?

(Naturally, not wanting to spend more than another $5 would imply
I want to get this right first-go :) so it's to see what's worked
before.)

--
Chris
From: commodorejohn on 1 Feb 2010 17:22
IDE doesn't *have* to require a 16-bit connection; people have built 8-
bit adapters for connecting IDE devices to small hobbyist projects.
http://www.mylinuxisp.com/~jdbaker/oldsite/SmallSys/8bitIDE.html is
one example. Just a thought.
From: Chris Baird on 2 Feb 2010 00:29
> IDE doesn't *have* to require a 16-bit connection; people have built
> 8- bit adapters for connecting IDE devices to small hobbyist
> projects.

This -is- for a 8-bit IDE interface. There's 8 bits for DATA0-7, then
another 6 I/O needed for A0-2, /CS0, /RD, and /WR.

What everyone else has built was full-on memory-mapped IDE controller
interfaces (they then sell the professionally-made devices to helpless
hobbyists for $50+...) Here, I've used software and straight-through
wiring w/ no semis to do the same thing, and still getting a respectible
14kB/sec transfers. To port this project to the Commodore there's just
the small matter of the CIA only providing 8 external I/O lines..

> http://www.mylinuxisp.com/~jdbaker/oldsite/SmallSys/8bitIDE.html is
> one example. Just a thought.

http://www.retroleum.co.uk/electronics-articles/an-8-bit-ide-interface/
was a great reference when builting the SYM-1 IDE interface.

--
Chris
From: Jim Brain on 2 Feb 2010 01:04
On 2/1/2010 3:13 PM, Chris Baird wrote:
> I've recently built a "$5" IDE harddrive interface for a
> Synertek SYM-1 (see<http://www.twitpic.com/photos/Sym_Biosys>),
> and now the idea is to bung one onto my C128.
> For that, I'll need 16 bits of I/O...
>
> I'm thinking this idea of using a 74LS373 would be the way to go:
> <http://www.compeng.dit.ie/staff/tscarff/Parallel_Port/SPP_interface.JPG>
> (Where this PC Printer Port expander uses STROBE, I'd be using
> the User Port's PA2, probably into a 74LS139.)
>
> Are there any examples (online) of this being done before for the
> Commodore User Port?
>
> (Naturally, not wanting to spend more than another $5 would imply
> I want to get this right first-go :) so it's to see what's worked
> before.)
>
Note that the link just shows how to latch and read 8 outputs and 8
inputs, not an IDE interface.

It might be tough to get enough IO for IDE out of the user port. I
think you only get 9 output lines on the user port.

You might find it easier to wire up 2 LS164s to one shift register
CLK/DATA line on the user port, and 2 LS166s to the other shift
register. Then, use the 9 output lines to trigger
R/W/CS0/CS1/A0/A1/A2/RESET. The 16 bit shift registers would be
attached to the 16 bit IDE interface.

If you did this, you could claim you have Serial ATA on your C128 :-)

Jim




From: Chris Baird on 2 Feb 2010 01:45
> I'm thinking this idea of using a 74LS373 would be the way to go:

Correction: 74LS245

(Once again caught out posting to Usenet at 4am in the morning..)

--
Chris
 |  Next  |  Last
Pages: 1 2 3 4 5 6
Prev: Replacement PLA-Eprom.
Next: Emulator - Bad lines and characters