As I was debugging serial communication between an ST Nucleo F303 board and a Raspberry Pi I found that the RPi baud rates are a way off on a RPi3. Then googled and found this git post that discusses the issue:
Here are some measurements to prove it at 115200 and 230400 bit/s baud rates. The slower speeds are equally off. Read more for working around this problem.
The new firmware is out for the detector and so is the new python scripts for datalogging.
What's new? Quite a lot:
Check out the details here: https://github.com/mvadai/muonhunter
Download the setup and programs available for the Muon Hunter kit as a single Raspbian image onto a minimum 8 Gb memory card. It's based on Raspbian Jessie.
It includes the AVR programmer feature and the datalogging interface, too.
here it is (now ver v0.3). See v0.3 notes.
The installation instructions are exactly the same as the Raspberry Pi image installation instructions found here:
The latest firmware update for the MCU is available on git. Now it displays the total number of GM counts, too. Thanks for the feature request, Paco. :) You can switch between the averaging and the total modes using the MODE button, plus fixed 2 little bugs.
Read more for the instructions.
We are going to program the ATmega168 microcontroller on the user interface board using the SPI interface on the Pi, so enable SPI. I mainly adapted this Instructables for the Muon Hunter kit.
These instructions work with v0.1 and v0.2 of the Muon Hunter kit.
This guide is for those who wish to configure their own Raspberry Pi.
If you have a working Pi skip to Step 4.
Download the full Raspbian image from here:
I always face this problem when working with a pi and there's no network around.
Majority of the web suggests a method which involves changing the IP settings on the RPi to static then noting down an IP address and connecting to the pi. However, there's no need to do that. You don't need to change the dhcp settings on the Pi if you follow this. I came across a nice feature of Gnome / Ubuntu which makes this direct connection very simple.
Here's a step by step guide under Ubuntu.
#2 Click "Add".
I've been working on this project for a while, check out this post about the user interface, this about the coincidence testing and this about the Geiger logger program. Finally, here's the previous anode type lead array detector I built.
The demo interface is not going to be accurate in the sense that you won't be able to see every hit when they are more frequent than 16 ms. If you need to count the individual us pulses, you'll need a different counter application to connect it to the detection circuit. I might actually have a go at it with some dedicated hardware at some point. That would be a natural way to improve on this project. Just for your demo / educational purposes I wrote a logger program for these applications in python which you can use on the Raspberry Pi to log these events. It's accurate enough to do the basic Rossi experiments with.
Not so long ago I tuned the pulse lengths and coincidence times for the anode detection coincidence detector circuit. You can find it here.
At that time it didn't even include an LED to give any visible information to the outside world. Today was the time to create a small LED-buzzer interface (if you can call that) for the muon detector for demo purposes. In the first coincidence detection prototype I built, I used a monostable 555 circuit to lengthen the (previously shortened) pulse form the GM tubes, since I had these 555s lying around. The GM pulse is shortened, because you can achieve more accurate coincidence detection that way, but for us those pulses are too short to see, they need lengthening. Since there will be a little beeper and 3 different LED signals (on 2 bi-coloured LEDs) plus a button in this project, I decided to use an ATtiny microcontroller instead of the 555s. The package is going to be smaller and it can source/sink the sort of current these LEDs or the buzzer need. Also, it's quicker to write some C code than going through the whole circuit design process just for some LED - buzzer - button business. I had an ATtiny44A lying around. It's a tremendous overkill for this project with its 4kb flash and 256B RAM. The code even with a little self test is less than 1 kb. Considering the size of the prototype case, this dip14 was the sort of size I wanted to solve this problem with.
The prototype is in the making, here's the a short video about the progress so far. This is the LED interface. The high voltage connectors are in the case, too.
CODE examples are on GitHub
About this blog
Welcome and thanks for visiting the Muon Hunter site. You've come to the right place, enjoy.