13 Mar
2023
13 Mar
'23
10:38 p.m.
I'm probing two DB25 connectors on the old IBM 5110 to figure out how to
programmatically jiggle some pins and get some serial IO going. I've
been working on writing a terminal emulator in its PALM machine code (now
that we have an excellent assembler for it) - I may go lazy and just have
it wrap around on the screen, instead of actually scrolling the screen (the
display circuit apparently has no scrolling, you have to DIY).
I've also written a kind of "synthesizer" to toy around with the timing of
its speaker. It's a video I'll be working on after the "domesticating the
home computer" stuff is done.
Anyway, as an option slightly cheaper than the Saleae, I'm trying the
32-channel version of the DreamSourceLab U3Pro32. It's not horrible, I've
24 pins hooked up so far. I debated on if 2x16's would be better.
Amazon is good about returns, but this little DSL probe is good enough,
I'll be keeping it.
DreamSourceLab DSLogic U3Pro32 USB-Based Logic Analyzer with 1GHz Sampling
Rate, 2Gbits Memory, USB 3.0 Interface, 32 Channels
-Steve
On Mon, Mar 13, 2023 at 8:12 PM Paul Koning via cctalk <
cctalk(a)classiccmp.org> wrote:
Gents,
I've been doing logic debugging (on a fairly primitive software defined
radio I designed back in 1999) with an old Philips logic analyzer. It's
not bad, certainly fast enough (I need 100 Msamples/s, it can do twice
that) and it's more than wide enough (I need 32 channels). But its capture
memory is microscopic so I struggle to see more than one or two
transactions, and I need to see more than that.
Some poking around shows various USB-connected logic analyzers for quite
low prices, and a number of them seem to have suitable specs. I also ran
across sigrok.org which seems to be an open source logic analysis
framework that can drive a bunch of those devices. Nice given that too
many of them only come with Windows software.
I suspect there are others that have not too expensive logic analyzers and
might be able to offer up suggestions or product reviews.
paul