HIL bus
| Company type | Proprietary technology |
|---|---|
| Industry | Computer hardware |
| Founder | Hewlett-Packard |
| Products | Computer bus architecture for human interface devices (keyboards, mice, trackballs, digitizers, tablets, barcode scanners, rotary controls, touchscreens) |
| Parent | Hewlett-Packard |
The HP-HIL (Hewlett-Packard Human Interface Link) represents a proprietary computer bus architecture created by Hewlett-Packard for connecting various human interface devices such as keyboards, mice, trackballs, digitizers, tablets, barcode scanners, rotary controls, touchscreens, and other peripherals to their HP 9000 workstation series. This technology remained in use until the mid-1990s, after which HP shifted to PS/2 interfaces, eventually adopting USB standards.
Supporting a maximum of seven devices chained together, the HIL bus operates at an 8 MHz clock rate. Devices generally feature both input and output ports to enable daisy chaining; however, mice are unique in that they possess only output connectors.
HIL interfaces were incorporated into HP PA-RISC and m68k platforms, early models of the HP Vectra, as well as certain HP/Agilent Logic Analyzers. Operating systems such as HP-UX, OpenBSD, Linux, and NetBSD include driver support for hardware utilizing the HIL bus.
The connectors employed by this bus include specialized 4-pin, 6-pin, or 8-pin SDL connector types, which resemble but are distinct from the widely used 8P8C modular plugs (commonly but incorrectly called RJ-45). Additionally, a 9-pin D-subminiature DE-9 connector may be utilized. To enable compatibility with PS/2 peripherals, HP provided an adapter (model A4220-62001) converting HIL signals to PS/2.
Specification
- HP-HIL Technical Reference Manual, HP part number 45918A