Which fact surprised you here? The fact that the Rigol isn't able to stream or the fact it's not mentioned on the wiki?
Both.
I see "continuous capture streaming" as the No. 1 defining feature of a USB scope. Without this they would provide no advantage over a standalone scope that I can see, other than cost + size.
Am I wrong? I've never bought one of these (eg a Hantek) before. The fact I can't find any solid information on this is making me wary.
The ability to capture and stream data only for short intervals, as the Rigol USB support appears to do, is little different in my mind to saving a screenshot or data capture from the scope onto a memory stick. The USB link to a PC is a live connection, there's zero point having it when you don't support any tasks more live than equivalent to saving onto a memory stick.
Depends. USB2 is rather slow and analog data doesn't compress well, so USB scopes that stream are rather bandwidth-limited.
All good. The theoretical limit of 480Mbit/s (60MB/s) is still a magnitude or more than what I actually need (eg 100K samples/s * 8 bits = 100KB/s + overheads).
On the note of compressibility: it would be possible to make some cheap lossless reductions to be able to stream more than the link would be otherwise capable of. Eg 4 bit deltas most of the time and then 8 bit raw samples when the value jumps by more than 4 bits. Alas it would have nasty practical implications: if your data changed to a less compressible form during a live capture then you would get buffer overruns (holes). So yeah, no to that
The closest thing I do know would be the range of devices offered by Saleae.
Thanks, I'll have a look.
I don't know whether the device supports this feature. Would definitely be nice to add to the libsigrok driver if it does.
Apologies: are you saying that the libsigrock driver doesn't have continuous capture support for the Hantek 6022BE?
Given that sigrok-cli straight out told me the Rigol didn't support continuous capture (only when I tried to run it), I'll have a poke at the source and see what it says about what devices support it.