Merge pull request #128 from RobertGawron/feature/architecture_diagrams

detailed readme

README.md

@@ -1,25 +1,37 @@
-# IonizationChamber
+# Ionization Chamber (a device to measure radioactivity level)
 
 **Current version is not fully tested and has many HW bugs.**
 
-When air's atoms are hit by radioactive particles, an ion-pair is produced. Ions has electric charge, if they are in electric field create by positive and negative electrodes, negative ions will move to positive electrode and positive will move to negative electrode. They will try to "meet each other" (I don't know how to explain it) thus creating a current. This current can be measured.
+## Principle of operation
 
-The current is proportional to amount of ion-pairs. Amount of ion-pairs is proportional to radioactivity level.
+When air's atoms are hit by radioactive particles, an ion-pair is produced. Ions has electric charge, if they are in electric field create by positive and negative electrodes, negative ions will move to positive electrode and positive will move to negative electrode.
+
+They will try to "meet each other" (I don't know how to explain it) thus creating a current. This current can be measured. The current is proportional to amount of ion-pairs. Amount of ion-pairs is proportional to radioactivity level.
+
+## Overall system architecture
+
+It is designed in a way that the device can work remotely, e.g. no connection via USB cable to user’s PC is needed.
 
 ![architecture](https://raw.githubusercontent.com/RobertGawron/IonizationChamber/master/documentation/diagrams/ArchitectureOverview-1.png)
 
+Remarks:
+* Amplifier has three stages (first stage is transimpedance amplifier, not FET transistor like most projects use). 
+* Amplifier has a separate power supply from 4x2V6 lithium batteries
 
-Hardware is made of:
-* Ionization chamber (two electrodes mentioned above)
-* Amplifier (first stage is transimpedance amplifier, not FET transistor like most projects use)
-* DC/DC converter to create 400V DC voltage for polarization of ionization chamber
-* Data acquisition
-  * Peak value measurement
-  * Actual value measurement
-  * Pulse counter
-  * Three diodes as user interface
-  * STM8 chip to collect data
-  * UART interface to send data to PC.
+ 
+
+### Power supply
+
+## Hardware
+
+PCB project was done in KiCAD.
+
+It’s a two layer board in size 10cm x 10cm.
+
+
+TODO
+
+## Software
 
 Software is made of:
 * Compilation via sdcc (has to be installed)
@@ -27,11 +39,18 @@ Software is made of:
 * Building project is done via makefile (has to be installed)
 * Communication with peripherals is done via STM8S_StdPeriph_Lib library (included in repository, no need to download it separably)
 
-Software is done in a way so that it's possible to develop it remotely (I'm using Raspberry).
-
-Below is the picture of actual version, it has digital part and DC/Dc converter, soldering is terrible, but it works.
+TODO extend this section.
 
 
+## Hazards
+
+* **The device exposes high voltage to user, although maximum current is very limited, it still poses health risk if the sensor external electrode would be touch.**
+* **Pins of switch to turn on/off amplifier power supply are very close to metal chassis. It’s possible that pins will be shorted-out by chassis, shorting-out lithium batteries resulting in fire.** I flied off this part of chassis and used insulation tape to avoid it.
+
+
+## Current state
+
+Below is the picture of actual version, it has digital part and DC/Dc converter, soldering is terrible, but it works. There’s no really reason to put this section here, but I like images and graphs :-)
 
 ![sensor render](https://raw.githubusercontent.com/RobertGawron/IonizationChamber/master/documentation/pictures/pcb_04_08_2019.jpg)