The ObsoNET is the first network card created for the MSX. In 2004, the hardware designer Daniel Berdugo and software developer Nestor Soriano joined forces to create a cartridge to bring ETHERNET standard to the MSX line of computers.

The cartridge is based on the Realtek RTL8019AS chip and uses a flash memory to host and execute a BIOS that allows the use of network commands from the Nextor operating system (compatible with MSXDOS). An EPROM stores basic configuration data for the RTL8019AS chip and a side connector is used to plug a network cable to your MSX. A GAL16VB is used to implement the logic required to activate and expose the cartridge to the computer.

The original version of the Obsonet was designed to fit a standard Konami cartridge case. This project implements a new version of the cartridge that fits the standard Patola cartridge case available in Brazil as well as the standard Konami cases available from multiple vendors WW.

Github repository with all files required to build the project: cristianoag/obsonet: Repository to host source files for the Obsonet Reloaded (github.com)