Although vintage gaming hardware may not possess the sophistication of contemporary technology, it does offer unique benefits. Retro gaming platforms, such as the Nintendo Entertainment System (NES), provide a sense of nostalgia and an opportunity to delve deeper into their internal mechanisms. The NES, with nearly four decades under its belt, is relatively uncomplicated by today’s standards. This simplicity renders it an ideal candidate for modifications, including the creation of an automated controller.
The original NES controller utilized a basic shift register to transmit button inputs to the system. Upon receiving a latch signal from the system, the controller would then extract the button states using the shift register, forwarding them individually to the system at a frequency of around 1000 times per second. It is feasible to replicate these signals without a physical controller. The automated controller featured in this project employs a CD4021 shift register, akin to the original controller. Instead of monitoring button states, this automated controller acquires inputs from a separate computer via a latching circuit. The custom computer system utilized in this project stemmed from the adaptation of cassette storage for a 6502-based computer, although any computing system can be employed.
This automated setup enables partial automation of gameplay. However, as the system lacks the capability to receive feedback on the game’s current status, precise timing and fine-tuning are essential for achieving optimal gameplay. This project does not stand alone. Similar techniques are utilized to develop tool-assisted speedruns, where gameplay is enhanced through external tools. While these speedruns are typically conducted on emulators rather than genuine hardware, they can still unveil intriguing game loopholes.
