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Full Version: Does anybody knows what is 3421 Control module (HP #82500B-A24) for HP-41
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Hi, Miki;

the 3421 is an HPIL compatible data acquisiton (plus more) unit. An HP41 with an HPIL can be used as a controller, BUT isf you have the 3421 ROM module, many ready-to-use HPIL based functions bcome available. The 3421 ROM function set eases the job of acquiring data.

Some guys here know it better. I just know it esists... q:^)


Luiz (Brazil)

Hi Luiz,

Thanks for the answer. Now I remember it but haven't realized that the unit was coming with a ROM module for 41C. I've seen it before but I remember it being the size of a PC. I just saw recently the ROM module without the DAU so I was confused.

Greetings from Calgary.

It is my understanding that if you have the Extended I/O module, this 3421 module is unnecessary. I have the XIO built into the HPIL (so the two modules together only take one port) and have used it extensively to control lots of equipment, including the 3421A data acquisition unit. Most of the equipment was on the HPIB (IEEE-488) bus though. I short description is in the "memories" forum.

Dear HP41 & HP3421 enthusiasts,

Controlling the HP3421 with HP41 needs the EXT-I/O Module or the 3421 DAC module. The last includes some special keyboard assignments - than the HP41 acts as an remote keyboard for the HP3421.

Usigng CLONIX you are able to programm the 3421DAC rom plus some other roms plus your individual user code software application inside an advanced one port solution...

Alternatively to HP3421 you can use me I/O-Board or the IL2000 System, which includes some more fardware features...

Regards from Germany - Christoph Klug