MERA 300

MERA 300 was a Polish-built 8-bit minicomputer family. It was first introduced in 1974 at the Poznań Trade Fair and Exhibition.
History.
The MOMIK 8-B (MERA) minicomputer had been designed in Poland in 1973. In 1974 the MERA 300 (MERA ZSM), based on the previous model, was introduced. The same year, at the Poznań International Trade Fair and Exhibition, twelve more models were displayed. MERA 300 was designed by dr. Waldemar Romaniuk and Janusz Popko.
About the family.
Family of the MERA 300 systems included:
System architecture.
MERA 300 included the next units:
MERA 300 series architecture.
Sets of MERA 300 (MERA 302, MERA 303) included:
The MERA 301 used magnetic tapes (PK-1 and PK-2) for data storage with a capacity of 0,5 million characters.
The MERA 305 was an extended version with DMA and a four-level interrupt system, with a total of 128 interrupts (4x32).
The MERA 306 was a more complex, extended version with features including:
In addition to the above, it was possible to attach other devices:
The computer's machine language consisted of 34 instructions, including arithmetical, logical and control instructions.
Data Input/Output.
Data input devices for the MERA 300 series were:
Data output devices:
Other input/output peripherals:
Software.
Basic system programs:
It should be mentioned that the MERA 300 RTX was not necessary while the MOTIS assembler ran, as it was able to work without an operating system.