Materials related to the historical Busch 2090 microcomputer such as a Raspberry Pi based tape emulator, example programs, an emulator, serial number records, etc.
You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
Heurekus b02d97b75f Merge branch 'master' into 'master'
Added new serial number and pictures

See merge request heurekus/Busch-2090-Projects!2
2 years ago
01 - first trace setup First commit of files 6 years ago
02 - PGM2 - record to tape - timing of signals - triggered with a Raspbery Pi divers 6 years ago
03 - PGM1 - read from tape emulated with a Raspberry Pi Image added 6 years ago
04 - Example Program - NIM Game Allow UTF8 chars in Python comments 6 years ago
05 - Busch 2090 Assembler Additional assembler instructions validated, demo program added 6 years ago
06 - Assembler - Example Programs NumberMind example program added 6 years ago
07 - Busch 2090 - PC Emulator - Ingo Rullhusen Update ChangeLog 6 years ago
08 - Busch 2090 - Serial Numbers Update --> corrected CPU date for 106873 2 years ago
LICENSE Create LICENSE 6 years ago Image link in updated 5 years ago


A Raspberry Pi based Tape Emulator, an Assembler and other tidbits for the Busch 2090 historical microcomputer

Project Image


This repository contains software, circuit diagrams and background information for several Busch 2090 related projects. Each project is contained in a separate directory:

  • 01 - first trace setup: Documents the first steps to explore the (digital) interface between the Busch 2090 computer and the 2095 cassette interface

  • 02 - PGM2 - record to tape - timing of signals - triggered with a Raspbery Pi: Contains a Python program and background information of how the 2090 can be triggered via a Raspberry Pi to send program data stored in its memory to the 2095 cassette / tape interface. This was only an intermediary step, the data was never read on the Raspberry Pi but just evaluated with a logic analyzer.

  • 03 - PGM1 - read from tape emulated with a Raspberry Pi: This is the MAIN directory that contains the Python program to download software from the Raspberry Pi to the Busch 2090, some sample programs to download and information on how to build the hardware to connect the Raspberry Pi via some of its GPIO ports to the 2090. Note: here is a video of how this process worked with a real casette tape.

  • 04 - Example Program - NIM Game: An example program to download to the 2090 via PGM1, a detailed commented version of it, a commented version in Libreoffice Calc format from which column B can be used to download to the 2090 and a Python version that runs on the PC.

  • 05 - Busch 2090 Assembler: A cross-platform assembler to conveniently translate Busch 2090 assembly instructions into 3-digit hex code machine code that can be downloaded to the original hardware with the tape emulator.

  • 07 - Micsim: A Busch 2090 for Linux (PC) emulator written by Ingo Rullhusen. GPL source and executable made available here are a perfect companion to test programms witten with the Busch 2090 Assembler from the directory above.

  • 08 - Busch 2090 Serial Numbers: A collection of serial numbers that give an idea of the number of sold devices.


Further background information such as PDFs of the original manuals and software to download to the 2090 is available at