caine

RadiationD-Cajoe for TRNG on Raspian [WIP]

Notes

• RadiationD-Cajoe board doesnt need a voltage divider - the VIN pin outputs 3.3v, confirmed with multimeter.
• The VIN pin is the pulse pin. Naming isnt intuitive.
• This project uses Pin #7 (BCM2835 pin #4) for GPIO reading - connect the VIN pin on the board to this.
• Have also got Pin read working in C with bcm2835.h, but WiringPi is cleaner and supports events.
• Pretty much every WiringPi event example uses an address operator on the callback function pointer given in parameter 3 of wiringPiISR(). I removed the operator and the callback function started working.
• The C code is inspired by this example.
• Existing examples of writing a kernel module to ingest measurements from a geiger on a Pi [kRad] used a different board to the RadiationD-Cajoe.

Progress

• GPIO event POC in Python3 and C

Next-Steps

• Acquire a source of beta radiation - Stronium 90 (like kRad uses) is hard to acquire in the UK, so I'll probably smash up some Radium glass or dismantle a smoke detector.
• Kernel Module for hardware rng sources to feed /dev/random
• Make files and other QoL stuff.