HP-IL

HPIL (Hewlett-Packard Interface Loop)
HP-IL connectors (on an HP-71B)
Type Peripheral data bus
Production history
Designer Hewlett-Packard
Designed 1980s
Manufacturer Hewlett-Packard
Superseded by USB (mid-1990s)
General specifications
External yes
Pins 2
Data
Data signal Token ring
Bitrate 160 kbit/s
(limited to 16 kbit/s) [1]
Max. devices 31
(with extensions up to 960)
Protocol Serial
HP-41CX connected to thermal printer and digital cassette drive via HP-IL

The HP-IL (Hewlett-Packard Interface Loop) was a short-range interconnection bus or network introduced by Hewlett-Packard in the early 1980s.[1] It enabled many devices such as printers, plotters, displays, storage devices (floppy disk drives and tape drives), test equipment, etc. to be connected to programmable calculators such as the HP-41C, HP-71B and HP-75C/D, the Series 80 and HP-110 computers, as well as generic ISA bus based PCs.

  1. ^ *Quick, R.D., Harper, S.L. (January 1983). "HP-IL: A Low-Cost Digital Interface for Portable Applications" (PDF). Hewlett-Packard Journal. 34 (1): 3–10.{{cite journal}}: CS1 maint: multiple names: authors list (link)