Rigol VISA Interface - Split from: Sniffing the Rigol's internal I2C bus - Page 1
Forum section: electronics / testgear

author: mark03
author_rank: Frequent Contributor
timestamp: April 01, 2014, 04:25:36 pm
content: As this seems to be the main Rigol-hacking thread, with plenty of twists and turns and side issues, allow me to add another...I've been reading up on the whole VISA and SCPI thing. To me it all seems mired in a 1980s/90s mindset, back when we were all thrilled to actually be able to communicate with our test equipment. E.g. "please, oscilloscope, send me a screen capture" (or a waveform) and after a little pause and fanfare music playing in my head, by george it does!!This is cool and all, and suffices, I'm sure, for many useful applications. But come on, we have a 480 Mbits/sec data link to play with!! (minus overhead and nonideal implementation factors) Shouldn't there be a mode in which the scope does nothing but stream raw(*) data onto USB or ethernet? Just imagine the possibilities! Vector signal analyzer, spectrum analyzer, ...(*Of course, you'd need to pick a 10- or 20-MHz-wide band and decimate to I/Q channels in the scope's FPGA)I'm guessing this would require a much deeper level of reverse-engineering of the firmware, unless there is a test mode buried in there. It would sure be nice if Rigol were to accidentally leak their firmware sources.

author: Rigby
author_rank: Super Contributor
timestamp: April 01, 2014, 07:15:32 pm
content: Quote from: mark03 on April 01, 2014, 04:25:36 pmcome up with a standard, implement it, open it, and test it, and i'm sure you'll have companies knocking down your door.LXI and VISA exist because they're good enough to get the job done. do you NEED 480Mb/s out of your scope? Do you NEED to feed 1M wf/s into your PC in real time?As soon as that stuff is needed or even desired it'll start showing up. If you disagree, please implement something and open it so that others can implement it on their hardware.

author: mark03
author_rank: Frequent Contributor
timestamp: April 02, 2014, 02:38:02 pm
content: Quote from: Rigby on April 01, 2014, 07:15:32 pmI very much doubt the sticking point is the work involved in implementing such a feature. The community would gladly do it for free, given suitable HW/SW documentation from Rigol. No, a far more plausible explanation is that Rigol would like to keep selling their other single-use test-equipment. A safe and conservative decision on their part.It's worth noting that hobbyists are already paying good $$$ for this sort of capability. See the openhpsdr project, which is nominally a direct-sampling HF transceiver but can also be used as a vector impedance meter. (This gets me to wondering how the Rigol front end would be for SDR... hmmm...)As to what is needed or desired, I've seen way too many market failures (like virtually the entire landscape of computing) to believe in a simplistic model of "customers have needs -> companies meet those needs for profit." Reality is more complicated, with plenty of feedback in both directions. But if I were going to try and over-simplify it, I would say that customers see what is out there, and only then decide what they need or want. (How many people desired a smartphone the day before the iPhone launch? And then how many, after trying their friend's iPhone?)

author: Rigby
author_rank: Super Contributor
timestamp: April 02, 2014, 02:47:23 pm
content: Well, since I was talking about creating a standard, and you're talking about implementation of the standard on a scope, I'm not sure that we're really going to come to a point in the middle in this discussion.