Tag: control

Recreates the Apple II Lego TC Logo interface card for controlling Lego Technic machines.

JCM showed 25 cards in stock on 2026-07-24. A working setup also requires a Lego 9750 Interface A with its IDC-20 cable and 9 V power supply, at least one compatible 4.5 V motor, and suitable Lego Technic parts.

Adds two independently writable pulse-width modulation outputs.

The project supplies a schematic, Gerbers, PCB design files, and kit or bare-PCB paths. The base address must be even; 0x04 is the documented example. Pulse frequency is the selected clock divided by 128.

Controls two hobby servos through two tightly decoded output ports.

The project supplies a schematic, Gerbers, PCB design files, and kit or bare-PCB paths. Although the servos can use the computer's 5 V rail, the maker strongly recommends an external supply because of loading and electrical-noise concerns.