FreeMCAn geiger counter on Raspberry PI (B+) as a kernel module and QT client

FreeMCAn-gc is a geiger pulse counter running on Raspberry Pi (B+). To get optimal performance the software is split into a hostware and a firmware part. The hostware is an user console program to collect and record the counting data. Alternatively a GUI related QT version is available. The firmware is a native linux kernel module driver which aquires all hardware related stuff. It sets up a periodic timer ISR and counts the geiger events via a hardware IRQ line (gpio).

Screenshot

Software and system requirements

Prerequisites:

• pidora
• Qt API (Version 5)
• g++/gcc - Gnu Compiler Collection

You have to post install the make environment, QT5 devel and the kernel development tools:

yum install qt5-qtbase-devel*
yum install qt5-qtbase-5*
yum install qt5-qtbase-x11*
yum install raspberrypi-kernel-devel*
yum install raspberrypi-kernel-headers*

Building and installing of kernel module (firmware)

Go into the firmware folder and type make. The kernel module can be loaded via insmod firmware_geiger_ts.ko (must be root!). Then start the hostware (must be root!).

To create access rights for specific users (run the hostware without beeing root) proceed as follows:

• Adjust the file 50-udev.rules according to the required user name and access rights
• Copy the file to /etc/udev/rules.d/
• Issue a udevadm control --reload-rules

To auto load the firmware during boot proceed as follows:

• Copy firmware_geiger_ts.ko to /lib/modules/$(uname -r)/
• Issue a depmod -a
• You may try to load the firmware via modprobe firmware_geiger_ts
• Check with lsmod or have a look at /proc/interrupts or check wheather /dev/freeMCAnPI exists
• Copy firmware_geiger.conf to /etc/modules-load.d/

Building the QT based hostware

• Proceed to hostware_qt folder
• Execute /usr/bin/qmake-qt5 hostware_qt.pro and then type make

Configuration

In a first step you may wish to configure the peripherals:

• The timebase signaling LED
  • See #define GPIO_TIMEBASE_LED 35 (default is the Raspberry Pi B+ PWR LED which is a conflict but will help you to start up with the software)
• The GPIO pin counting signal
  • See #define GPIO_INTERRUPT_PIN 23

The License

LGPLv2.1+