While the GPIB standard has electrical requirements not met by the RP2040, this microcontroller has proven adequate in-practice, without line drivers. The exact board used for this project is the "Adafruit KB2040 - RP2040 Kee Boar Driver". Load the KB2040 with Adafruit's default  'Circuit Python' package along with the Adafruit libraries. With these steps complete, Drag-n-Drop the code linked to this project (rename it to 'Code.py') into the flash memory of the KB2040. It will be compiled on-chip. The connections from the GPIB port (a male Centronix-type 24-pin D-sub connector) to the Adafruit KB2040 are:

GPIB DIO1 to DIO7 (Centronix connector Pins 1-4 and 13-15) connect to KB2040 D0 to D6
GPIB DIO8 (Centronix connector pin 16) is unconnected
GPIB NDAC (Centronix connector pin 8) connects to KB2040 MOSI
GPIB NRFD (Centronix connector pin 7) connects to KB2040 MISO
GPIB DAV (Centronix connector pin 6) connects to KB2040 D7
GPIB ATN (Centronix connector pin 11) connects to KB2040 D8 (prototype breakout board lists the HPIB name (MRE) vs the GPIB name (ATN))
GPIB REN (Centronix connector pin 17) connects to KB2040 D9
GPIB EOI (Centronix connector pin 5) connects to KB2040 D10