Add textual explanations

docs/group_assignments/group2/assignment6.md

 ---
-title: Electronics design. Group 2 Work. 
+title: Electronics design. Group 2 Work.
 summary: Group work. Testing microcontroller.
 show_authors: true
 authors:
@@ -14,23 +14,41 @@ authors:
 # Group work for week 6
 
 This week we tested a microcontroller power usage with a multimeter.
-We demonstrated the use of an oscilloscope in 
-[week 4](https://fabacademy.org/2023/labs/oulu/group_assignments/group2/assignment4/).
+We have previously demonstrated the use of an oscilloscope in
+[week 4](./assignment4.md).
 
-For the power measurement, we applied the [code](https://fabacademy.org/2023/labs/oulu/students/akseli-uunila/assignments/week_04/#source-code) written by Akseli Uunila
-
-We measured the power consumption from the usb connection 
+To measure the current we used a modified USB extension cable.
+The voltage wire has been cut to allow connecting the multimeter in series.
+This way we can use any USB power supply.
 ![Powermeasurement5](./assets/assignment6/power5.jpg)
 
-We did the measurement for three different stages of the program.
+For testing the board, we uploaded
+[Akseli's code](https://fabacademy.org/2023/labs/oulu/students/akseli-uunila/assignments/week_04/#source-code)
+written for the Seeed XIAO RP2040 in week 4.
+
+The code has two stages that can be changed using serial communication.
+
+1. Blinks the on-board NeoPixel with two colors
+1. Blinks the small built-in LED on/off
+
+We changed one color to be full white (255,255,255) to see the maximum power usage.
+The other color is a medium blue (25,25,180).
 
-In the first one, the color of the neopixel led was set as bright white color, which drew highest amoung of current.
+So in total four states ranging from both LEDs off to the full white NeoPixel.
+We measured the current for each of the states.
+
+In the first one, the color of the neopixel led was set as bright white color
+which drew highest amoung of current.
 ![Powermeasurement1](./assets/assignment6/power1.jpg)
 
-In the second one, the color of the neopixel led was set as blue color, which drew less current
+In the second one, the color of the neopixel led was set as blue color
+which drew significantly less current.
 ![Powermeasurement2](./assets/assignment6/power2.jpg)
 
-Finally, the neopixel led was not burning, which drew least current.
-![Powermeasurement3](./assets/assignment6/power3.jpg)
+In the third one, only the small built-in led is on
+which is almost the same as the next state.
+<!-- TODO image of the small led blinking -->
 
+Finally, neither of the LEDs was on, which drew the least current.
+![Powermeasurement3](./assets/assignment6/power3.jpg)