【Hitachi】 System Software for Early Computers

 In the era of early computers such as HIPAC 101, HITAC 301 and HIPAC 103, operating systems which control the whole computer did not exist. In those days, we only had programs that performed individual processing tasks, such as symbol input routines and interpreters. Symbol input routines converted programs into machine languages by inputting them from punch cards or paper tapes, and interpreters executed pseudo-instructions held in the storage while converting them into machine languages.
 With HITAC 301, for example, if a program written on a paper tape was input, a symbol input program called SIP converted it into a machine language and stored the result in storage. When SIP completed processing of the final instruction, the computer would temporarily stop running. So, the user had to press the start button to execute the program. This meant that the computer was controlled through human intervention.

 HIPAC 101, announced in 1958, was shown at a computer exhibition organized by UNESCO in June 1959, in Paris, and shipping began in July 1960. HITAC 301, Hitachi’s first transistor-based computer, was delivered to Japanese Electronic Industry Development Association in May 1959. HIPAC 103 was a parametron computer developed for scientific and engineering computation. The first model was delivered to Kansai Electric Power in December 1961.

 Table 1 shows the system software for HIPAC 101, HITAC 301 and HIPAC 103.

Table 1 System software for HIPAC 101, HITAC 301 and HIPAC 103
Model System software
HIPAC 101 HISIP 101: symbol input routine
Assembly SAP-II (Symbolic Assembly Program)
Converts a symbolic program punched on 80-column cards into a machine language, and output the result to 80-column cards while punching the cards.
Input program SIP (Symbolic Input Program)
Converts a symbolic program punched on a paper tape into a machine language, and stores the result in storage.
Interpreter GITS (General Interpretive System)
xecutes a program with pseudo-instructions stored in storage while converting it into a machine language.
HISIP 103A, B: symbol input routine
It is equivalent to an assembler, and provides control instructions that are not converted into machine languages, including those for program reading and debugging.
Allows a processing change through a statement for debugging and switch operation on the control board.

  Table 2 shows a list of major library programs for HITAC 301. The program library for HITAC 301 was roughly divided into six types of programs: system program, business computation practical program, engineering computation program, subroutine for engineering computation, engineering computation utility routine, and programs for education and demonstration. These programs were further subdivided and organized into middle classes and small classes.

Table 2

Table 2 "Major library programs for HITAC 301"