22 Mar
2012
22 Mar
'12
12:02 p.m.
On Mar 22, 2012, at 1:03 AM, Chuck Guzis wrote:
On 21 Mar 2012 at 12:12, David Riley wrote:
Well, the 880 is also a pretty basic drive. :-) Gets the job done,
and it was cheap for me to acquire, so... yeah.
The way I see it, though, the Pertec interface is practically made
for a 6522 or 8255 or any chip that supports hardware data strobes.
You can almost emulate that functionality as interrupts with most
modern micros, and some of them will even allow you to use them as
DMA strobes (though I suspect you'd have to throw it through a one-
shot first).
Pertec is a pretty simple interface with
handshake lines. I would
imagine you shouldn't have much trouble. An FPGA may be overkill
(certainly harder to work with 5v); you may find it even easier to
just use a microcontroller. My Cipher F880 runs on just a Z80
internally, nothing fancier than that.
I believe the 990 uses 2 Z8002 CPUs and the 995 uses a Z8002 +
80C186, so definitely more horsepower is useful. Move up to a standalone PIC32 chip and you get DMA
channels and up to
128K of on-chip RAM.
A lot of the ARM Cortex-M[3|4] chips are along the same lines. You
might actually check out ST's STM32F4DISCOVERY board, which could be
had for free at one point (I think it's about $15 right now). It
has a pretty decent Cortex-M4 on it, has most of the I/O broken out
onto pin headers, and has a built-in USB programmer (which has support
in OpenOCD and also has connections to act as a standalone SWD tool).
It's kind of a bummer I haven't seen any Arduino stuff using the
XMEGA chips yet; that line certainly brings the AVR into the
current decade. DMA, properly modularized I/O, etc. Open-source
programming tools for it are still a little flaky, though.
- Dave