CodeNet Protocol

The CodeNet protocol is a very simple protocol to send data and executables to a C64 computer via ethernet. A CodeNet server is normally listening on UDP port 6462. The protocol uses a request-reply mechanism to ensure that the server has received each packet. Every valid CodeNet packet is replied with a packet with the same sequence number and the service field set to ACK (0x01). Optional fields are not replied.

CodeNet Protocol Header:
0 1 2 3
0xCA1F Sequence Service
Adress ¹ Size ²
Data ²

¹ - required by DATA, FILL, JUMP
² - required by DATA, FILL


0x00 - PING - Ping server.
0x01 - ACK  - Packet acknowledgement.
0x04 - DATA - Send data to C64 memory. Data size is limited to 128 bytes.
0x05 - FILL - Fill C64 memory with byte.
0x06 - JUMP - Jump to C64 memory adress.
0x07 - RUN  - Run C64 program.

© 2010 Graham