V 1.2.2

Geiger counter PC-GM3 and PC-GM4 program.


Known Bugs
Previous versions


This program is for the very low consumption Geiger Muller counter PC-GM3 or PC-GM4 described on this page (in French). This page gives all information to build the hardware part of the counter. For information, the current consumption the counter is around 20µA in normal mode.

To download the program on the counter, you must use a JTAG probe MSP-FET430UIF.

Program for the Geiger Muller counter PC-GM3 and PC-GM4

Download Version 1.2.2: Same as version 1.2.1, but fix a problem with the push button handler.

You'll find in the directory ...\release\exe:

  • The exe files Geiger1_bargraph.a43 and geiger1_bargraph.txt for the version with bargraph management (__FIX_PCB_BARGRAPH TRUE in lcd.h)
  • The exe files Geiger1.a43 and geiger1.txt for the version without bargraph management (__FIX_PCB_BARGRAPH FALSE in lcd.h)

image image

Version 1.2.1: Same as version 1.2.0, but returns the model and serial number following after a "V" command, returns the the battery voltage and other internal data following the commange "G" (Get Internal Data), bargraph management with the modified PCB (#define __FIX_PCB_BARGRAPH).

Version 1.2: The same features as the version 1.1 but with a management of internal error codes.

Version 1.1: This program carries out a Count Per Minute (CPM) and a count by 24H. It displays the number of CPM and the average of pulse per 24H (At the end of 24 hours, otherwise, since the starting up of the counter). It displays the result in µSv.h on the basis of the CPM and on the average of the counting per 24H. Eventually, you have to adjust the "conversion factor" value (CPM <-> µSv/h) according to your Geiger-Muller tube. The couting is sent to the host by the serial port com (USB emulated). In this way, you can make your statistics on your computer by using the GeigerPC software.


The counter displays data on a dedicated LCD display. The image above (click to enlarge) shows how the display is used in normal operation. Pushbuttons allow to interact with the GM counter to validate the alarms, the errors and to change some settings. For clarification, see the documentation (in French).

display Display with the not modified PCB.
Display with modified PCB. Use with the bargraph version software.

Technical documentation

Environment and target platform


Communication with the counter

Serial link (COMx), 9600bps, 8 bits, 1 stop, Parity none.


Described in the functionnal documentation (in French) and the page dedicated to the GeigerPC software.


Known Bugs

You can report the bugs of the program by using the "contact" on the home page.