Sony HBI-232
This page was last modified 09:42, 25 May 2023 by Mars2000you. Based on work by Gradius2 and Msxholder and others.


The Sony HBI-232 is a RS-232C interface including a cartridge and a manual.

The adapter has a fixed cable attached that provides a DB-25 Male port.

It is just one of the three MSX Serial add-on adapters to use RS-232C BIOS 2.0 (the other being the ASCII MSX-Serial 232 and Repro Factory HBI-232MKII). The ROM included in the interface contains also the RS-232C BASIC instructions.

The adapter has a switch on the front to select Modem or Terminal. This effectively provides an integrated null-modem function, which would normally be needed for connecting to a Terminal. As such a straight serial cable can be used with a Terminal instead.

Where MSX serial solutions with BIOS 1.x use IO ports, and only one such adapter may be used at a time, with BIOS 2.0 memory mapped I/O is used, and multiple adapters are allowed.

Brand Sony
Model HBI-232
Year 1986
Region Japan, Germany, Spain, The Netherlands
Launch price ¥19,800
Package content Serial Interface adapter
User's Manual
Emulation Emulated


Sony HBI-232 box and content
Sony HBI-232
Sony HBI-232 closeup
Sony HBI-232 back
Sony HBI-232 box
Sony HBI-232 manual
Sony HBI-232 PCB
Sony HBI-232 PCB underside

External links