That oscilloscope software

Will now plot the two waveforms from the scope in a window. It'll discover the scope by searching ports. But it's having trouble acquiring a 'long' memory from the scope. There are 2 options on this scope, a short (500 samples) memory and a long (12,500 or 25000) memory. The communication between the PC and the scope is by short message and (potentially long) reply. There's an RS232 port and a USB host socket on the scope. The reply that contains the sample memory is one long string, with the sample data presented as pairs of bytes. For the short memory, the message is just over 1,000 bytes long. The long message is around 25,000 or 50,000 bytes long! At least, it should be. My program only gets the first part of the message.

I tested the scope's reply against HyperTerminal on win and minicom from Linux, and there does seem to be an issue with a truncated reply. I'm not convinced it's the fault of the scope, but most of the times it happens, the scope locks up, requiring a power cycle to make it usable again. I must check again, but either the null modem cable between serial ports, or the USB A-B cable and HyperTerminal does allow a full 12,500 sample reply to be acquired. The USB connection is a bit odd. The VendorId is 0558, allocated to Truevision Inc in the Linux USB ID list. The Instek setup.inf has the same vendor id and a product id of 2009, and simply registers the scope as a USB serial device. In desperation, I had a look inside the scope. It seems surprisingly well built! The USB host socket connects to a Philips ISP1362 USB On-The-Go controller, so I'm guessing whatever OS is running on the nearby BlackFin processor is repsonsible for those Vendor and Product IDs.

I was having no luck with the long sample memory reply on my Linux desktop at all. Truncated every time, at around 1,000 characters - 24,000 short! I was using

modprobe usbserial vendor=VVVV product=PPPP

to get the scope to be recognised as /dev/ttyUSB0. I tried on my laptop - it has a slightly different Linux setup on it - and the scope was recognised as /dev/ttyACM0 - a USB modem (supported by the cdc-acm module). I've had a couple of limited successes with this method, so I'm bringing both laptop and desktop up to the same software revisions. RXTX is giving me a problem though: it has a problem opening the handy gnu.io.rxtx.properties file, due to a (real!) bug. I'll sort that out, try sending a patch off to the developers, and see how I get on from there.

It's not looking very encouraging at the moment, I'm hoping for a piece of software anybody could just download and start using, whether on Windows or Linux (no means to check anything else), and it has been a bloodbath so far. Well, a nosebleed, at least. More later!