Dominik-Workshop / KD-23MTS

STM32 based oscilloscope, AiR 6 sem PWR

KD 23MTS

This project is a simple oscilloscope built using an STML476RG microcontroller and a 4" TFT SPI 480x320px V2.1 LCD with an integrated ILI9488 driver and touchscreen with an XPT2046 driver. It was developed for the Robot Controllers project during the 6th semester of AiR at PWR.

Project Goals

• 2 channels
• FFT (Fast Fourier Transform)
• RMS, peak-to-peak, and frequency measurements
• Horizontal and vertical cursors
• Auto mode trigger (channel 1)

Connections

• LCD

  STM pin	Component pin	Signal description
  PA6	SDO(MISO)	TFT_MISO
  PC9	LED	TFT_Backlight
  PB3	SCK	TFT_SCK
  PA7	SDI(MOSI)	TFT_MOSI
  PC4	DC/RS	TFT_DC/RS
  PA10	RESET	TFT_RESET
  PC8	CS	TFT_CS

• Touchscreen

  STM pin	Component pin	Signal description
  -----	T_IRQ	T_IRQ
  PC2	T_DO	Touch_MISO
  PC3	T_DIN	Touch_MOSI
  PB12	T_CS	Touch_CS
  PB10	T_CLK	Touch_SCK

• Rotary encoder

  STM pin	Component pin
  PA9	ENC_A
  PA8	ENC_B
  PC0	ENC_BTN

• Oscilloscope channels

  STM pin	Component pin	Signal description
  PC5	BNC connector 1	Channel 1
  PB1	BNC connector 2	Channel 2

• Test signal output

  STM pin	Component pin	Signal description
  PB0	GEN OUT connector	1kHz test signal

Touchscreen calibration

1. Navigate to the file oscilloscope.c and locate line 35. Remove the comment slashes (//) to activate the function touchScreenCalibration();. Save the changes and upload the code to the device.
2. Open a Serial monitor on your PC. You should observe the following prompt:

   Press the screen at the yellow squares that appear,
   then paste the following line into stm32_adafruit_ts.h :
   

3. Interact with the LCD screen by pressing on the three yellow squares. Upon completion, the calibration values will be displayed. For example:

   #define  TS_CINDEX            {1777297, 4469, -237569, 908499464, -171651, 9601, 587895710}
   

4. Follow the instructions provided in the previous step by copying and pasting the displayed line into the file stm32_adafruit_ts.h. After pasting, comment out line 35 in oscilloscope.c, and re-upload the modified code to the device.

Used tools:

Used Libraries

• Touchscreen Library: stm32_hal_graphics_display_drivers - This library was chosen for its effective calibration function and reliable touch detection.
• LCD Library: ILI9488-DMA-SPI-STM32 - This library was selected for its high display speed. It was modified to use a frame buffer to prevent flickering.

(No need to install any libraries; the appropriate files are included in the project.)

Authors:

• Dominik Pluta
• Kamil Winnicki

Special thanks

Special thanks to Eryk Możdzeń, who helped with programming.