Dual Serial 232 Interface (DS232)

A two-port RS-232 serial card for the ADAM - the serial half of Eric Pearson's MIB238 on a board of its own, for a machine that needs the ports but not the parallel port, boot PROM socket or memory addressor.

What serial buys

• A modem, which is how the machine reached bulletin boards then and reaches the internet now through a WiFi modem.
• A terminal, or a modern computer standing in for one - which is how disk images are moved on and off the machine.

Like Pearson's other designs it uses modern MAX238-family transceivers, so it runs from the 5V rail alone rather than needing the supplies the 1980s cards wanted.