Wednesday, May 02, 2007
When I programmed in 6809 assembler
I have been asked how could I have programmed in 6809 assembler since a ZX-81 computer used the Zilog/NEC Z80 CPU. So to clarify things, I only ever programmed in BASIC on the ZX-81, but in the mid eighties I had a job designing and programming realtime controllers for fruit grading and handling machinery. These controllers used the 6809 processor. It was a very interesting and challenging job. The code was created on a system running Flex 9 OS, burned to EPROM and then tested in the real hardware. Debugging was done using a logic analyser.