Shimadzu C-R4A Chromatopac

This is probably some control computer for gas chromatograph. It works as data collector, integrator, data processor and viewer. It is based on Intel 8088 processor and has 512kB of RAM. Such large amount is needed to buffer data incoming from chromatograph before writing it to the floppy disk.
Video system allows to plot diagrams as well as text using terminal-like commands. Built-in amber CRT is used. The computer has ADC to get measurements, a multi-pin GPIO board, RS232 and current loop ports to connect printer or other I/O devices. Two 720kB 3.5" floppy disk drives allow to store system and data.

Manufacturer Shimadzu

Origin Japan
Year of unit 1986
Year of introduction ??
Type Control Computer
CPU: Intel 8088
RAM: 512kB
ROM: 8kB
 - RS232
 - Current loop
 - Parallel GPIO
 - ADC input
 - Keyboard port.
OS: CP/M-like

Built-in amber CRT
Built-in membrane keyboard


The OS bootbale from floppy  (when it starts, it performs POST and then displays "SET SYSTEM DISK" message) is a CP/M 80-like system with BASIC interpreter built into command processor. There is no PIP nor CCP in ith explicit form, system boots from floppy and starts BASIC program (all chromatography software is in BASIC) or allows to write own commands. It is possible to make system bootable disk with only command processor.

Floppy disk is in 1024 bytes per sector format not recognozed as any known CP/M format, but its internal structure resembles heavily-modified or cloned CP/M. Types of files are identified not by extensions, but by users which files belong to. DIR command displays files for all users.

Power supply unit is quite rigid. Two switching blocks supply high-current 5V and 12V DC. Additional transformer gives 16V AC which can be rectified to any other voltages needed. This is used probably with ADC.