PC-1401 PC-1402 PC-1421
The PC-1401 was the first of a series of pocket computers with a new concept.
It combined the advantages of a BASIC programmable pocket computer and a scientific calculator. Nevertheless, it was much thinner than, for instance, the PC-1500, and well worth its price.
Therefore, the PC-14xx series was very successful, especially among students.
The PC-1401 was developed based on the PC-125x series, thus it
possessed the same BASIC core capabilities. In addition, it had a separate
calculator mode, in which it could be used like any of Sharp's scientific
calculators, such as the EL506H.
For this purpose, the right section of the keyboard had 18 additional math keys, and it could be used as any standard AOS entry calculator. Moreover, a set of statistics functions was implemented.
In BASIC mode, the additional math buttons could be used as shortcut keys to enter the BASIC keywords of these math functions. A downside was the small display with only 16 characters, which made it somewhat hard to keep track of your BASIC program while programming.
As the PC-125x series, the PC-1401 was based on the SC61860 8-bit CMOS
microprocessor, clocked with a 576 kHz ceramic resonator circuit, and the same
display driver chip (SC43536). It had 4.2 KB RAM (two HM6116 2k x 8 chips plus
some bytes in the display driver chip) and 40 KB ROM (SC613256). All chips and
other components were soldered onto a single PCB. The RAM of the PC-1401 could
not be extended by modules.
The PC-14xx series consisted of various models; here, only those directly
derived from the PC-125x hardware are described. At least three different models were widely available in the West:
PC-1401: This was the first machine of the series, released in 1983.
PC-1402: Released about one year later. Basically the same machine, but
with more RAM. One of the HM6116 chips had been replaced by a D4364G 8k x 8
chip, resulting in 10.2 KB RAM (9678 bytes for BASIC).
PC-1421: This machine was also released in 1984. As the PC-1401, it had
4.2 KB RAM (3454 for BASIC). However, it was powered by a later release of the
CPU and clocked with a higher clock rate (768 kHz), which made it one third
faster. From the software's point of view,it was equipped with special math
functions for business/financial matters.
Together with the PC-1401, the CE-126P thermal printer and micro cassette
interface unit was introduced. It was alcaline battery powered and could print
24 characters per line on special thermal paper.
Special thanks to Roman von Wartburg and his Website, who provided us all this information.