11 Jun
2013
11 Jun
'13
11:43 a.m.
On Jun 11, 2013, at 12:17 PM, Philipp Hachtmann <hachti at hachti.de> wrote:
Oh, sure. I think it makes much more sense for what you're doing.
And it allows for a single-chip solution (plus some passives).
Hi,
Neat! I'll be interested to see what you come up with.
I'd assume you're thinking along the
lines of a simple digital PLL
using the capture/compare functions of the timers? That could be
done with a VERY small AVR/other micro indeed.
I think of doing it interrupt
driven in software :-)
I already made some rough estimations on the timings involved. If you wanted
to make it more "retro", you might be able to do it
fairly simply with a 6502 and 6522. :-) Still more modern than
the RK05's internals, though, and I have no idea how much space
is available in the box there.
I will use a 20MHz ATmega-AVR ATmega48 or ATmega88.
The reason is that I already have that part. It's available for less than EUR 3 and
does the job. I know it's overkill. But I'm not designing for mass-production
where every penny costs thousands. I want to get the job DONE and the thing RUNNING.
So I use the MCU that I have on stock and where I already have made some schematic
templates in Eagle.
Everyone who wants it "more retro" is free to do so. But why has it not been
done yet??? :-P
Of course! Just throwing a slightly whimsical twist out there on
the 8-bit micro idea. I myself don't have any kind of RK05 (I
only recently got an RL02 and don't have any kind of controller or
media for that, let alone an RK05 and associated parts, so it's
entirely an academic suggestion). Besides, implementing it with
a 6502 is *cute*, but to make it anywhere NEAR period-appropriate
(and it would obviously have to be a retrofit, since the 6502 was
introduced in 1975), you'd have to rely on building it from pulls,
which is silly when you can buy an AVR new now and for years to
come.
- Dave