SAPI-1

The SAPI-1 was a computer produced in the former Czechoslovakia by Tesla since 1980.
It was designed by Eduard Smutný (hardware) and his brother Tomáš Smutný (software), and based on the Intel 8080/2 MHz clone (and later Z80). The SAPI-86 was also developed as an 8086 clone of the PC.
The SAPI-1 had a modular construction with modules:
3 versions of SAPI-1 were produced:
integer Micro-Basic was stored in ROM, as well as simple machine code monitor, tape was used as main storage device, using single block recording.
MIKOS (mikro kazetový operační systém - micro cassette operating system) with better machine code monitor was stored in ROM, any other programming language was loaded from tape, using blocks of 255 data bytes.
ROM contains CP/M booting sequence, CP/M is booting from 8" Shugart floppy disk drives. Position of VideoRAM was moved from 3800 to E800 to allow CP/M running.
The "Z" version of SAPI-1 ZPS 3 used Z80 processor clone instead of 8080 clone, video with 64 characters per line instead of 40.