It uses clever data compression, essentially recording just changes on each pin, rather than the state of each pin at every clock.
When I bought this unit it had no serial decoding capabilities.
I did get a surprise one day when the supply tripped for apparently no reason. This is a 100 MHz USB MSO with two analog channels, eight digital channels (nine if you include the external trigger which can be displayed along with the other digital channels), and 4 mega-points of memory.
Turned out an unused supply was current limited to 0.000 A. Chris Svec also has a GW Instek power supply: I have a GW Instek dual output power supply which is just okay - it's got a loud fan that runs all the time, and the voltage output seems to drift a bit, but that could be because I nudge the sloppy control dials unknowingly. The sampling rate is 100 MSa/sec (one-shot = 10 MHz) which is more than enough for the embedded work I do.
Graham Whaley writes: On a similar vein to the LOGIC little logic analyser, I surveyed the market for small cheap units a few years back, and we decided on the from Intronix It is a 34 channel logic analyser that uses time compression to store samples in its rather small buffer, so if you have a slow moving signal you can get quite long traces.
It will also go up to 200MHz external clocked, or 500MHz internally clocked.