Sharp PC-1211

The Sharp PC-1211 is the first pocket computer ever released, marketed by Sharp Corporation in March 1980. The computer was powered by two 4-bit CPUs laid out in power-saving CMOS circuitry. One acted as the main CPU, the other dealt with the input/output and display interface. Users could write computer programs in BASIC.

A badge-engineered version of the PC-1211, the TRS-80 Pocket Computer (model PC-1), was marketed by Radio Shack in July 1980 as the first iteration of the TRS-80 Pocket Computer with just a marginally different look (outer plastic parts in black, not brown, gray display frame)

Technical specifications

 * 24 digit dot matrix LCD
 * Full QWERTY-style keyboard
 * Integrated beeper
 * Connector for printer and tape drive
 * Programmable in BASIC
 * Uses four MR44 $1.35 V$ Mercury button cells
 * Battery life in excess of 200 hours
 * 1424 program steps, 26 permanent variable locations (A-Z or A$-Z$) and 178 variables shared with program steps
 * Built out of off-the-shelf CMOS components, including SC43177/SC43178 processors at $256 kHz$ and three TC5514P $4 Kbit$ RAM modules

Accessories

 * CE-121 Cassette Interface
 * CE-122 Printer

TRS-80 Pocket Computer ("PC-1")
A badge-engineered version of the Sharp PC-1211 was marketed by Radio Shack as the original TRS-80 Pocket Computer. (This was later referred to as the "PC-1" to differentiate it from subsequent entries (PC-2 onwards) in the TRS-80 Pocket Computer line.)

Introduced in July 1980, the "PC-1" measured 175 × 70 × 15 mm and weighed 170 g, and had a one-line, 24-character alphanumeric LCD.

The TRS-80 Pocket Computer was programmable in BASIC, with a capacity of 1424 "program steps". This memory was shared with variable storage of up to 178 locations, in addition to the 26 fixed locations named A through Z. The implementation was based on Palo Alto Tiny BASIC.

Programs and data could be stored on a Compact Cassette through an optional external cassette tape interface unit. A printer/cassette interface was available, which used an ink ribbon on plain paper.