This page was last modified 04:15, 10 August 2022 by Mars2000you. Based on work by NYYRIKKI and Sd snatcher and others.

Many MSX-computers have LEDs in them and sometimes it is possible to change the LED's status by software.

Type Remark
Power This LED (if available) is directly connected to the power supply unit and can't be changed by software.
Caps Lock Available in most MSX compatible computers and can be changed trough PPI port C (I/O #AA), bit 6
Kana Lock This LED is available in Japanese MSX computers and its status can be changed using PSG register 15, bit 7
Pause This LED is available in some MSX2, most MSX2+ and all Turbo R models. In the Turbo R it can be changed trough I/O #A7, bit 0
CPU (turboR) Can be changed through I/O #A7, bit 7
Disk drive MSX disk drives have leds, but usually diskdrive leds are linked to disk motor signal, so turning the led on/off also toggles disk drive motor on/off. The way to change the led/motor status depends of MSX model & manufacturer. For example in Panasonic MSX tR Diskdrive led & motor control can be accessed trough address #7FF2, bit 4 in slot 3-2