Sharp PC-1211
Tandy/Radio Shack TRS80 PC-1
Sharp PC-1211 Pocket Computer, also sold as the Tandy TRS80 PC-1
Display - 24-digit alphanumeric dot matrix Liquid Crystal Display, with yellow filter.
In calculator mode it can display in scientific format 10 digits mantissa and 2 digits exponent.
Functions - Calculator and 1424 step BASIC language programmable computer.
26 Fixed memories.
Up to 178 Flexible memories (shared with program memory).
Battery back-up of CMOS memory.
A cassette recorder can
be connected using an adapter cradle, allowing programs to be saved to audio cassettes. Also a printer & and cassette adapter was available, see photograph below, thus providing the full needs of a pocket computer.
Power supply - 4x Mercury button cells, giving "approx. 300 hours" use. The power consumption is 0.011 watts.
Semiconductors - CMOS LSI, including:
- CPU 1 - SC43177.
- CPU 2 - SC43178.
Two CPUs (Central Processing Units):
Three TC5514P, 4 K-bit RAM.
Size 175 x 70 x 17 mm (6.9" x 2.75" x 0.7").
Introduced - 1980.
Made in Japan.
There was also a Sharp PC-1210 model, with less memory, which was introduced shortly after the PC-1211.
The PC-1211 is included here to show the culmination of ten years of development of the hand-held calculator. Although by this time there were many programmable pocket calculators, starting with the Hewlett-Packard HP-65 of 1974, this can legitimately be described as a pocket computer since, unlike the programmable calculators, it has a full "QWERTY" keyboard and is programmed in the high-level BASIC computer language.
With the rear cover removed showing the "operation" pcb. CPU 2 is the chip in the centre of the board.
The "operation" pcb has been hinged downwards to show components on its rear, including the three RAM memory chips on the left.
The "keyboard & display" pcb is revealed, which has the CPU 1 chip on its left, and
three display chips (with built-in RAM) from top-centre to right.
The PC1211attached to the CE-121Cassette Interface unit, which allows programs to be stored on audio cassette tapes and recalled later.
The red plug goes to the cassette recorder "Mic" socket, the grey plug goes to the
"Earphone" socket, and the black plug goes to the "Remote" socket.
The PC1211 attached to the CE-122 Printer & Cassette Interface unit and sitting in the de luxe carrying case.
Sharp were pioneers in hand-held calculators in 1970 with the EL-8 and were very successful in the calculator business through the turbulent years of the 1970s. Ten years on from the EL-8 they were still at the forefront of technology with this, one of the first pocket computers.
For comparison, there are details of the EL-8 below.
