stm8L touch library usage tutorial

1. Check the touch library documentation and select the chip according to your needs (mainly supporting several keys): STMTouch Driver User Manual

One channel is one button. For example, STM8L101F supports 3 buttons. You can add more buttons by expanding the button. For details, refer to:

Guide to increasing the number of touch sensor buttons.pdf

2. Download the corresponding official touch library STM8L_STMTouch_Lib_V1.1.0, and copy the following two folders to your own project folder

3. Select a project similar to your own project to open. For example, if I want to make a touch light with 1-4 buttons, I choose STM8L101K3_Ex01

Open: Projects - Examples - STM8L101K3_Ex01 - EWSTM8 (I used IAR) - Example.eww

4. Run Make after opening. Generally, make succeeds with 0 errors.

5. Open the corresponding config file. In my case, it is the tsl_conf_stm8l.h file. The following settings need to be made in it:

There are many parameters in this file. I will configure them when I use them later. I am not sure about them now.

6. Open tsl_user.c, touch the application function of the library, make modifications, and read the program step by step. I have the habit of adding comments, which is convenient for looking back.

Here's how I first read a program, breaking it down step by step:

7. After reading the user.C file, you will have a general idea of ​​the parameters of the touch library. Generally speaking, it involves the following preparation steps:

Determine the pins according to the requirements and set the number in the conf file. Set the channels, banks, groups, and objects in the user. Finally, get the user function. Call the main function in main or interrupt to determine which button is triggered. For details, you need to go through the main of the routine:

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Now that we have finished reading the main function, let's continue to look at the functions below:

After checking main.C, we roughly know the mode of this library. In the action user function, we can judge which button is pressed to execute the desired program. In addition, the touch library has a TIM4 heartbeat timer. We can modify the code, change the time or replace the timer as needed. We can also execute some process codes in the timer interrupt as needed.

Load the program into the board and it executes well. The sensitivity can be adjusted by the relevant parameters in conf.H. You can try it out.

I went through it quickly this time, focusing on the function implementation, without going into detail. Some parts of the official library code are confusing, and some key parts are not explained as they should be. The experience is average. Compared with the dedicated touch IC of general manufacturers, the advantage is good scalability, most STM8 can be used. I will try to transplant the touch solution to other chips such as 51 when I have time, and we will communicate together then.