[Retr0id]

Ooh! The faster speeds would be very welcome, I was bothered by the slowness of the AR488 but I assumed that was just how GPIB was (I had no baseline to compare to). I'll switch over when I get a chance.

That user's project also looks very interesting - My TDS684A's CRT seems to have died, and rather than fix it I could switch to using a software scope.

[inferiorhuman]

HPIB/GPIB itself should be reasonably fast, I think NI had some later revisions that were even faster. If I had to guess there will be two big hardware bottlenecks with the open source dongles: almost all of the 8-bit and cheaper ARM boards only do USB FS (12 Mbps, so 1MByte is pushing it) and most of those boards don't have any hardware acceleration for managing a parallel bus like GPIB. Even switching up to a Mega/Due form factor means you could potentially read the status and entire data byte in one read.

FWIW I'm working on a buzzword compliant stack for ARM MCUs interleaved with writing some HALs for Embassy. It'll be interesting to see how it compares. While I'm waiting on a replacement Chinese clone I decided to order a few more boards (Atmel, NXP, Renesas, STM), level shifters, transceivers, and whatnot from DigiKey to play around with.

[xyphro]

The upcoming V3 adapter reaches even more than 1 MByte/s with my fastest instruments. Unless you connect long GPIB cables to it, because capacitive load slows down GPIB as it self regulates speed down in the way GPIB is designed.