On 2019-10-03 11:13 a.m., Reginald Beardsley via Groups.Io wrote:
FYI I've decided to commission the design of an OSHW board to plug onto a $3 Arduino Nano with footprints for a BNC, USB B and either a 2x12 0.1" header or a PCB mount Centronics connector. The 2x12 header will allow easily making up custom GPIB cables using ribbon cable and IDC connectors. I made a 2 device adapter using an Uno. Soldering the ribbon cable to the Uno was quite a pain because of the way the cable mapped to the pins. Hence the 2x12 header.
The BNC is for a strobe signal for the 34401A and similar and the USB B to provide a more robust connector than the mini USB on the Nano.
A later version will use the Mega 256 with relays, T&H, RTC, etc.
My intent is to make OSSW/OSHW GPIB-USB-HS adapters available for <$10 without the need to find old GPIB cables.
The chap I'm having do the board is pretty busy with a couple of other projects, so it may be a while before the board design gets posted online.
The Nano will handle 10-12 GPIB devices as the 328P operates at 5V and can source or sink 40 mA per pin. At $3 + connectors for a GPIB-USB-HS adapter, the ATMEGA 328P deserves more respect than I had been giving it. They make great glue for old TTL interfaces. Most other MCUs won't drive TTL loads. Interestingly, the Nano is cheaper than a single IDC Centronics connector.
I also did a Nano-based GPIB project, but using driver ICs:https://github.com/qu1j0t3/gpib-adapter
AR488 is an extension of the Prologix command set. ...