SD pin monitor

November 29th, 2007

This is a program (Read: Quick and dirty hack) that I wrote when debugging my MIDI interface for Pushpin. Unlike Pushpin, which requires proper MIDI data to react, this program gives a clear visual and audible indication if anything is happening on the SD pin.
If the voltage read on the SD pin is high, the screen goes black, if it is low, the screen goes white. When nothing is connected, the screen is black due to pullup resistors.
On low-to-high transitions, the program makes a beep. If alot of data is coming in, the screen will make a pattern, and the sound will be more noisy. (Simply put, it reads the status of the pin and spawns it to the screen and sound chip)

This program only useful for people doing very special things with their Gameboy’s link port. ;)

The few lines of code used to make this program are included. Compile with RGBDS.


2 Responses to “SD pin monitor”

  1. Gameboy Genius » Blog Archive » Pushpin Gameboy MIDI cable build report (Failed) says:

    [...] link port, which is what Pushpin is using to read MIDI data. The program can be downloaded here: SD Pin Monitor. However, when trying it out, my sound card suddenly stopped working. No$gmb froze when using [...]

  2. Cementimental says:

    Download is dead :( Would be cool if you could fix; I got Pushpin working already but I’d like to play with this thing, have some ideas for potential misuse of it! :)

Leave a Reply

If you'd rather contact me directly, please use the following e-mail address: It appears that you have Javascript disabled. Please enable it to see my e-mail address.