THREE GERMAN
EDUCATIONAL COMPUTERS

For a few years in the early 1980s a new category appeared in German department stores: the educational & experimentation computer — a complete “learn how a computer works” machine for interested laypeople, not a bare kit. Three contenders stood out, and each wins a different crown.

Busch Microtronic

1981 · DM 379 (later 299)

🎓 The educational computer

CPUTI TMS1600, 4-bit

Clock500 kHz

Runsinterpreted VM · 41 instructions

Specialtypowerful high-level ops — Harvard: mult, div, time, RND, …

Memory256 words / bank

Speed≈ 114 instr/sec

I/O4 in · 4 out (4 LEDs) · 2 input buttons (G/H) · 1 Hz, Carry & Zero LEDs · 6-digit display · hex pad · RESET button

Exp. bus— none (only a GPIO-like DIP socket)

Cassetteadditional 2095 (into that socket)

Wins because: a near-RISC, almost fully orthogonal instruction set — powerful programs in tiny memory — and manuals ideal for children and teenagers.

Kosmos CP1

1983 · DM 198

🔧 The experimentation computer

CPUIntel 8049, 8-bit

Clock6 MHz

Runsdecimal interpreted VM

Specialtyrealistic ISA — von-Neumann: indirect addressing & jumps, self-modifying code

Memory128 → 256 cells

Speed≈ 3,200 instr/sec

I/Omany fast GPIOs · 6-digit LED · membrane

Exp. busyes — module bus (CP2/CP3/CP4/CP5)

Cassetteadditional CP2 module

Wins because: the richest, fastest I/O for real measurement & control — though a system of squandered potential (a few more opcodes would have worked wonders).

Philips MasterLab

1983 · DM 449

⚙️ The real CPU trainer

CPUNational INS8070 (SC/MP III)

Clock4 MHz

Runsnative machine code

Specialtytrue 16-bit ops — hardware MPY & DIV

Memory1 KB RAM

Speed≈ 147,050 instr/sec

I/Oonly SA/SB in + F1–F3 out (LEDs) · 8 output LEDs · 8-digit display · RESET + ON/OFF (the only power switch)

Exp. busyes — but needs a custom decoder

Cassettebuilt-in — on board (no module)

Wins because: the only one programmed in raw machine language — the fastest and most “real” — but it arrived late (1983/84) and dearer.

⏱SPEED — MEASURED INSTRUCTIONS PER SECOND (log scale — the MasterLab runs ~1,290× the Microtronic, ~46× the CP1)

Busch Microtronic

≈ 114 ips · 1×

Kosmos CP1

≈ 3,200 ips · 28×

Philips MasterLab

≈ 147,050 ips · 1,290×

⚖THE VERDICT — EACH WINS A DIFFERENT CATEGORY

None of the three subsumes the others. The Microtronic is the clear educational computer (near-RISC instruction set, manuals made for kids); the CP1 is the experimentation champion (plentiful, fast GPIOs for measurement & control); the MasterLab is the only genuine CPU trainer (native code, interrupts, blistering speed). Scored across nineteen equally-weighted criteria, it is remarkably close — and together they are a fascinating piece of technical history that existed in this form nowhere else.

42Microtronic

38Kosmos CP1

37MasterLab

▶ Read the full story

The complete all-in-one English write-up — 22 pages with a print-ready PDF, benchmarks, and the modern revival of all three machines — translated from the original German LOAD articles.
github.com/lambdamikel/german-educational-computers-of-the-80s