Retro Ultra Replica

Microcomputer project based on the Intel 8085 microprocessor working with UDI_22 (ESP 32 Universal Digital Interface). In the first version we are attempting to emulate several historical computers, such as the Altair 8800, Imsai 8080, HP 5036A, and similar models.

The main goal is to enhance our detailed understanding of computer systems’ functions, but, above all, to evoke and recreate the atmosphere of the amazing period between 1973 and 1979 when people had the opportunity to encounter the first versions of personal computers.


Intel 8085 processor

Instruction table:

Monitor ver. 1.2

> ?

A ON|OFF                 - Enable/Disable Automatic register display
B [bp address]           - Set/Display breakpoints
C <src> <dest> <size>    - Copy memory
D <address>              - Display memory in assembly format
E <address>              - Edit memory
F <start> <end> <value>  - Fill memory
G [address]              - Begin/Resume execution
H <start> <end>          - Send out memory in Intel HEX format
I <port>                 - Input from port
L [address]              - Load image into memory
M <address>              - Display memory in hex dump format
O <port> <data>          - Output to port
R [rp value]             - Set/Display program registers
S ON|OFF                 - Enable/Disable Subroutine trace
T ON|OFF                 - Enable/Disable Trace mode
U [address]              - Set/Display program base address

Memory mapping

monitor         0000 - 0fde
blink           0fdf - 0fff (delay: call 0ff2)         
boot1           1000 -
boot2           todo: read "intelhex"
BASIC           1800 - 399f
...             39a0 ?
62256 (32k)     8000 - ffff
                FFA0    ; Debugger RAM (Monitor)

6264  (8k)      A000 x