“Wireless World Magazine in January and June 1981 published this design. Reproduced on solderless breadboards using the original Monitor ROM
The Nanocomp 6809 was a simple microcomputer design published in Wireless World magazine in 1981, with a 25 key keypad and 6 digit 7 Segment LED display. I built a version of this using PCBs and wire wrap in 1981. Now re-built using the original Monitor ROM on solderless breadboards. See step by step progress of the project on the Nanocomp Playlist https://youtube.com/playlist?list=PL0HI91x0gPoGBl-kXYaOYuHD8poIxmHG3.
The Wireless World Nanocomp 6809 project was published in July 1981. Scans of the original paper-based articles are included in the Files section. The full January 1981 and July 1981 Wireless World issues are available online but are not quite as clear as the scans.
I had started to build a Motorola 6809 based micro earlier in the 1981 but then adapted the design to incorporate the memory map used by the Nanocomp and adopted the keypad and 7 Segment LED display design so the Nanocomp 6809 Monitor ROM could be used. During the COVID Lockdowns, I came across the original PCBs and wiring pen boards in the attic. They were quite corroded, and the key caps had gone missing but the EPROM with the monitor will still readable using an EEPROM programmer. “