The

Texas Instruments Texas Instruments Incorporated (TI) is an American multinational semiconductor company headquartered in Dallas, Texas. It is one of the top 10 semiconductor companies worldwide based on sales volume. The company's focus is on developing analog ...

Hex-Bus interface (sometimes used unhyphenated as Hex Bus and with varying capitalization) was designed in 1982 and intended for commercial release in late 1983. It connects the console to peripherals via a high-speed serial link. Though it was prototypical to today's

USB Universal Serial Bus (USB) is an industry standard, developed by USB Implementers Forum (USB-IF), for digital data transmission and power delivery between many types of electronics. It specifies the architecture, in particular the physical ...

(

plug and play In computing, a plug and play (PnP) device or computer bus is one with a specification that facilitates the recognition of a hardware component in a system without the need for physical device configuration or user intervention in resolving reso ...

, hot-swappable, etc.), it was never released, with only a small number of prototypes appearing in the hands of collectors after TI pulled out of the market. Several Hex-Bus peripherals were planned or produced. A WaferTape drive never made it past the prototype stage due to reliability issues with the tapes. The 5.25-inch floppy drive also never made it past the prototype stage, even though it worked. Prototype DSDD disk controllers and video controllers were also made. A 4-color printer-

plotter A plotter is a machine that produces vector graphics drawings. Plotters draw lines on paper using a pen, or in some applications, use a knife to cut a material like Polyvinyl chloride, vinyl or leather. In the latter case, they are sometimes k ...

, a 300-

baud In telecommunications and electronics, baud (; symbol: Bd) is a common unit of measurement of symbol rate, which is one of the components that determine the speed of communication over a data channel. It is the unit for symbol rate or modulat ...

modem,

RS-232 In telecommunications, RS-232 or Recommended Standard 232 is a standard introduced in 1960 for serial communication transmission of data. It formally defines signals connecting between a ''DTE'' (''data terminal equipment'') such as a compu ...

interface, an 80-column

thermal A thermal column (or thermal) is a rising mass of buoyant air, a convective current in the atmosphere, that transfers heat energy vertically. Thermals are created by the uneven heating of Earth's surface from solar radiation, and are an example ...

/ink printer, and a 2.8" "Quick Disk" drive were the only peripherals released in quantity, mostly for use with the TI CC-40. All Hex-Bus peripherals could be used with a TI-99/4A when connected through the Hex-Bus Interface, through direct connection to the TI-99/8, or through direct connection to the Compact Computer 40.

Devices

*HX-1000 Printer/Plotter *HX-1010 Printer 80 *HX-2000 Wafertape drive *HX-3000 RS-232 interface *HX-3100 Modem *HX-3200 Centronics Printer Interface *HX-5102 Disk Drive/Controller * Quick Disk QD-02

Connector

The DockBus of the TI-74 is electrically identical.

References

{{reflist

External links

The TI-99/4A Archive
Hex-Bus Specification
The TI-99/4A Home Computer Page
64K bank-switched cartridge project
TI HEX-BUS SD Drive Interface
Computer-related introductions in 1983 American inventions Computer connectors Serial buses