Controlling electronics with the Commodore 64 user port - Part 1
Controlling electronics with the Commodore 64 user port - Part 2
Controlling electronics with the Commodore 64 user port - Part 3 with Arduino
Controlling electronics with the Commodore 64 user port - Part 4 of 4 with Arduino and LCD and OLED
Controlling The C64's User Port
Blink an LED with the Commodore User Port: C64 Electronics Programming Part 1
Commodore 64 User Port to solenoid
C64 - Connecting devices safely to the user port - Arduino data transfer
C64 User Port - a trivial example
C64 userport, controlling 12 bits
Commodore 64 controlling a mains-powered device.
C64 userport 10 parallel bits
C64 Opto Isolation User Port to Ardiuno part 1
Arduino Project: Commodore 64 interfacing across the user port
Loading programs into a Commodore 64 using SDHost-64 connected to the User Port
How to integrate Commodore 64 with Arduino
2 in 1: Running cartridges with 64NIC+ ethernet card on Commodore 64
Commodore Userport LED Project
RS232 on Commodore 64 | Connect C64 with a PC | Easy way