Encyclopedia > IEEE-488

  Article Content

IEEE-488

Hewlett-Packard Instrumentation Bus (HP-IB) was an early computer bus standard developed by Hewlett Packard for connecting electronic measurement and test equipment to computers. Other manufacturers copied it, calling their implementation General-Purpose Instrumentation Bus (GP-IB). It was later standardised by the IEEE as IEEE-488.

It allows up to 15 intelligent devices to share a single bus, with the slowest device participating in the control and data transfer handshakes to drive the speed of the transaction. The maximum data rate is about one megabit per second.

Other standards committees have adopted HP-IB (American Standards Institute with ANSI Standard MC 1.1 and International Electro-technical Commission with IEC Publication 625-1).

To paraphrase from the HP 1989 Test & Measurement Catalog (the 50th Anniversary version): The HP-IB has a party-line structure wherein all devices on the bus are connected in parallel. The 16 signal lines within the passive interconnecting HP-IB (IEEE-488) cable are grouped into three clusters according to their functions (Data Bus, Data Byte Transfer Control Bus, General Interface Management Bus).

In June 1987 the IEEE approved a new standard for programmable instruments called IEEE Std. 488.2-1987 Codes, Formats, Protocols, and Common Commands. It works with the IEEE Standard Digital Interface for Programmable Instrumentation, IEEE 488-1978 (now 488.1). HP-IB is Hewlett-Packard's implementation of IEEE 488.1.

It was used by computers such as the Commodore PET.

External Link

based on FOLDOC



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Planning statistical research

... the design of our research. This last approach can become very technical, so we will postpone its discussion until optimum experimental design[?]. See also: statistics ...