Eprom Programmer

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In 1986 I decided to "have a go" at building my first project from scratch. I had a sample MC6803 that I obtained from Motorola. This micro controller is supposed to be an MC6801 with failed internal ROM. So I made an EPROM programmer using my trusty MK14, a kit I assembled which was my introduction to microprocessors, and programmed a 2716 with all of the machine code of Motorola's Lilbug 1.0 that I had laboriously typed in from a listing. I configured the 6803 for expanded operation with the 2716 and was dismayed when it never worked. But when I reconfigured the 6803 to run as if it were a 6801 in its single chip mode, "Lilbug 1.0" popped up magically at 300 BAUD on to my terminal. The first thing I did was  dump the Lilbug machine code to a file and compare it to my hand typed version. There were two bytes I had typed incorrectly and unfortunately, one of them was in a critical path of programme code which prevented Lilbug from getting started. From that beginning, I built a new board with the 6803 over to the left and lots of empty board to the right. I made sure that it worked in single chip mode first and then expanded outwards to the right adding whatever I needed for a particular application. Initially, I programmed applications in machine code. But I soon tired of that and modified the 1802 cross assembler of the Forth system to be a 6801 assembler. It is now primarily my EPROM programmer. It can programme an MC68701 in the processor socket as well as up to 64kbyte EPROMs in the ZIF socket.