Update README

README.md

@@ -1,22 +1,42 @@
-# stm32f4-heater
+# stm32l4-heater
 
 ## Purpose
-This is a PoC application of a Heating Element System that Controls in a closed
-loop a heating component. 
+This is a Proof-of-Concept (PoC) application of a Heating Element System that is controlled in a closed loop, using a PID controller. To determine the heating element control signal, we first read the current temperature and based on the error, the generation of the signal occurs.
 
-A PID controller is used to determine the heating element control signal 
-having first read the current temperature.
+In order to control the component, a zero crossing approach is used to set the durations open of a TRIAC.
 
-In order to control the component a zero crossing approach is used to set the
-durations open of a TRIAC.
+## Design
+For the purposes of this project, a Linear Power Supply (LPS) is used instead of a Switch-Mode Power Supply (SMPS), due to the ease of design for the PoC circuit, despite being less efficient.
 
-
-## Notice
-This is a PoC implementation, in a real applications various parts of the hardware/software
-should be altered to include a better solution.
+In a real-world application, considering the fact that an STM32L4 is occasionally used in low-power applications, most probably a SMPS should be considered to power the PCB, since the power would likely be one requirement that needs to be concerned about.
 
 ## Schematic
 ![schematic](./doc/stm32l4-heater.png)
+The schematic was designed using [Kicad](https://kicad.org/) and the related files are also availabe [here](./pcb/stm32l4-heater/). Inside the [doc/](./doc/) dir, a PDF file of the schematic can be found too.
+
+## Code
+The code is available on this [directory](./code/stm32l4-heater/) and it contains a STM32CUBEIDE project.
+
+## MCU - STM32L4 
+The MCU that was selected is the STM32L412K8U6, with the following specifications:
+* Distributor: Mouser.com
+  *  URL: https://gr.mouser.com/ProductDetail/STMicroelectronics/STM32L412K8U6?qs=l7cgNqFNU1iqBWKB4DHwcA%3D%3D
+  *  Price (24/12/2024): 
+       | Qty. |   Unit Price    |
+       | ---- | --------------- |
+       |  1   |        2.4€     |
+       |  10  |        1.52€    |
+  * Stock (24/12/2024): 3774
+* Package/Case: QFN-32 
+
+The reasons for this selection are as follows:
+  * First and foremost, it has all the necessary hardware for our application (not many requirements to fill in this very case).
+  * A common package makes it easy to select another MCU in case this one is out of stock in the future, and it is also easy to solder, even with a heat gun.
+  * An affordable price, less than 2€ per unit.
+  * Sufficient stock at the moment of speaking.
+
+## Notice
+This is a PoC implementation, in a real applications various parts of the hardware/software should be altered to include a better solution.
 
 ## License
 Everything that is related to hardware in this repository is licensed under the CERN-OHL-S-2.0 with the added condition that it may not be used for commercial purposes without prior permission from the license holder.