This is a Raspberry Pi HAT that implements a PC-style parallel port. GPIO pins are organized as data, status, and control registers. The HAT includes a buffer chip that converts from the GPIB 3V3 logic to signals that conform to IEEE 1284. A 26 pin IDC header on the board connects to your DB25 connector. A parport-gpio driver and device tree overlay integrate the HAT with the Linux parport driver stack.
I wanted to use a parallel port based cooled astronomy camera, but preferred to use the compact and low-power Raspberry Pi over a PC at the telescope. Parallel ports are simple devices. Why not build one?
This is a playground (and dump) of stuff I made, modified, researched, or found for the Flipper Zero.
There's a lot of everything in here, from customized apps, BadUSB scripts, hardware specs for modders, GPIO interface shenanagains and interface pinouts, hardware troubleshooting, sound and music stuff, and sub-GHz captures and dissections for just about everything. It's an impressive collection.
piscope is a logic analyser (digital waveform viewer) for the RasPi. It shows the state (high or low) of selected GPIO pins in real-time. Uses the services of the pigpio library. pigpio needs to be running on the Pi whose GPIO are to be monitored. The pigpio library may be started as a daemon.
Install pigpiod on the RasPi: sudo apt-get install pigpiod pigpio-tools
Install PyScop on your workstation: yay -S pyscope
Start pigpiod: sudo pigpiod
Run pyscope on your workstation
export PIGPIO_ADDR=raspipiscope
This GPIO Pinout is designed to be both a quick and interactive reference to the Raspberry Pi GPIO pins, plus a comprehensive guide to your Raspberry Pi's GPIO interfaces. It also includes dozens of pinouts for Raspberry Pi add-on boards, HATs and pHATs.