-----Original Message-----
From: cctalk-bounces at
classiccmp.org [mailto:cctalk-
bounces at
classiccmp.org] On Behalf Of Tony Duell
Sent: 05 January 2014 19:46
To: cctalk at
classiccmp.org
Subject: Re: MFM Control Signals and RD disk size
I can try that, wish I had a logic analyser that
let me monitor what a
real disk does...
You don't need a very high sample rate to hadle the ST412 interface
signasl,
so jsu aobut any logic analysr would do. They are not
that hard to find
now,
but if you buy a second-hand one, make sure it comes
with the pods.
Finding
pods is not at all easy. Making them is perhaps a
little easier, but still
a lot of
work.
I am told you can now get a USB-interfaecd thing that turns a PC into a
logic
analyser. Since I want ot keep PCs ase far from my
electroncis bench as
possible, I've not looked into these, but I have heard good reports of at
least
some of them.
-tony
In the first instance I am going to try implementing someone else's Verilog
logic analyser directly in the FPGA, that won't help analyse what an
existing disc does quite so well, but it may give me some clues.
I have always wondered about the USB ones, good to hear some are OK, any
recommendations you have heard of? I see a few "proper" ones on Ebay,
usually without pods though or for a bit more than I can spare.
Regards
Rob