Intel 8085 rack system

The 8085 circuit diagram.
Intel 8085 Assembler The 8085 assembler is available in a number of different versions however when I designed and build my 8085 system I did not have the money required to buy one so I wrote my own! I had previously written a dis-assembler for the Zilog Z80 cpu on my ZX81 in BASIC and later converted it to machine code without an assembler. This ran in a 1k ZX81.

For the Rack system I already had in my posession a Zortech C complier so I wrote some programs in C and also at that time I ordered a 5 1/4" floppy from a shareware magazine with the AD86 assembler dis-assembler and debugging environment.

The D86 and A86 runs in a DOS windows window or from the command line in DOS. The two programs are listed here: D85, i8085ins.set and A85. This is the AD100 boot loader: Rom25.8. Etc.. More to follow. I.e. the boot program which lists some instructions burned into an EPROM chip by hand on a breadboard (!) for initialising the ad100 USART in order to downloading the operating system from the PC, and the operating system it'self.