Z80 Assembly 65: Implementing Network Addressing (The Network Layer)

The OSI Model and the Network Layer The Network Layer (Layer 3 of the OSI model) is responsible for logical addressing (e.g., IP addresses) and routing data packets between different networks. This is where your simple 4-byte addresses come into play. Goal: To wrap the Link Layer frame (Part 64) with a header that includes a Source Address and a Destination Address. Defining the Packet Structure Our simple network packet (often called a datagram) needs to sit inside the Link Layer frame and contain the necessary addressing information. ...

September 27, 2025