BRG SLK 80 microcomputer

• Data collection and preparation
• Office applications
• Text editing
• Process control

Structure

Central unit

Byte-organized machine (8 bpB)

• control unit:
  • Zilog Z80or U880 microprocessor, clock speed 2.5 / 4 MHz
    • 16 bites címsín, 8 bites adatsín
    • 3 register pairs (2*8 bits), 3-3 16-bit and 8-bit registers
  • TTL additional circuits
  • real-time timer 100 ms – 0.4 μs
• main store:
  • 32 KB DRAM; expandable to 64 KB
  • 2 – 4 KB EPROM
• calculator: ALU built into a microprocessor
• interface capable of controlling up to 8 interface cards

Periphery

• backup:
  • built-in KM-3 cassette recorder (2 kbaud)
  • SLK-80 MF mini floppy disk (125 / 250 kbaud)
• external devices:
  • CRT monitor or TV set
  • alphanumeric keyboard
  • sound generator (40 Hz – 200 kHz)

Operation

Automatic power-on (or after Reset) process:

• Copying the loading program from the EPROM to the 2 KB starting address range of the main memory
• Copy the bootloader from the floppy disk to the main memory address #3000 and start it
• Initialize B/K ports, clear screen
• loading the operating system into main memory and starting it.

Block data transfer between the main storage and the backup storage was considered an innovation.

Screen resolution: 24 lines, 40 / 80 chpl.

Character types: normal, flashing, inverse-flashing, underlined, quasi-graphic.

Program set

• operating system: no
• compilers:
  • assembler
  • BASIC

Self-developed external device operating program, including

• SLK-4
• SLK-4 AR
• LK-4

to replace data collection and preparation products.

Historical curiosities

According to the original design, the MCD 1 floppy disk developed in the factory was intended as a backup storage device (see its product sheet), but due to changes in development circumstances, this was not realized.

To circumvent the embargo, Z80 clones were produced in several socialist countries (GDR, USSR, Bulgaria); the GDR version designated U880 was used in the SLK 80.

The SLK-80 achieved an average efficiency of 98% at room temperature.

Resources

Product guide number BRG 406 (The document is from the collection of István Vincze)