Pico Eval Board
Contents
Overview
The Pico-Eval-Board is an overall evaluation solution designed for Raspberry Pi Pico. With 3.5inch 65K colorful LCD display and misc helpful onboard components, this evaluation board allows you to try almost every on-chip peripheral of the RP2040, eliminating the messy wiring. It is an ideal choice for users to fast get started with the Raspberry Pi Pico, as well as the RP2040 chip.
Features
- Standard Raspberry Pi Pico header supports Raspberry Pi Pico series boards
- 3.5inch resistive touch screen, 65K colorful, bringing clear and vivid display effect
- Standard 3.5mm audio jack, for headphones or other audio peripherals
- Micro SD card slot through the SDIO interface, faster access speed than SPI interface
- Integrates battery header and recharge circuit, allows it to keep running without wired power supply
- Other rich resources like a buzzer, photoresistor, and RGB LED...
Specifications
Operating voltage: 5V
- Touch Type: Resistive
- Communication bus: SPI
- Display panel: IPS
- Controller: ILI9488/XPT2046
- Resolution: 480×320 Pixels
- Display colors: 65K colorful
- Pixel size: 0.153 × 0.153 mm
- Display size: 73.44 × 48.96 mm
- Dimensions: 86.00 × 57.20 mm
What's on board
- Rapsberry Pi Pico header
- for direct attaching to Raspberry Pi Pico
- LCD connector
- for connecting the 3.5inch IPS LCD
- Mirco USB connector
- CP2102 communication or battery recharge
- 3.5mm audio jack
- headphone interface
- Micro SD card slot
- using SDIO interface, faster access speed
- PH2.0 battery header
- for connecting 3.7V Li-po battery
- CP2102
- USB to UART converter
- SP0503
- diode for protecting the chip from ESD
- PCM5101A
- stereo audio DAC chip supports analog audio output
- 74HC4040
- counter chip for clock frequency division
- 74HC04D
- inverter chip
- 74HC4094
- serial to parallel data converter
- ETA6096
- battery recharger, 1A recharging current
- ICM20948
- 9-axis motion sensor, allows posture sensing
- LSD0204
- voltage level translator, ensuring safe communication between chips on different operating voltage
- XPT2046
- resistive touch controller
- W2812B
- RGB LED, so cool
- Passive buzzer
- controllable sound frequency
- User key
- a user-defined key, connects to GP2
- Reset key
- Pico reset
- Photoresistor
- converting light intensity to voltage signal, measuring light intensity
- Indicators
- PWR: power indicator
- TXD: CP2102 UART TX
- RXD: CP2102 UART RX
Pinout
Hardware connection
Please take care of the direction when you connect Pico accroding to the USB port. You can also check the pin of Pico and the Eval board when connecting.
You can connect display according to the table.
| Eval Board | Pico | Description |
| VCC | VSYS | Power Input |
| GND | GND | GND |
| SDIO_CLK | GP5 | SCK pin of SDIO interface, |
| LCD_DC | GP8 | Data/Command control pin (High: Data; Low: Command) |
| LCD_CS | GP9 | LCD select pin, low active |
| LCD_CLK | GP10 | CLK pin of the SPI |
| MOSI | GP11 | MOSI pin of SPI |
| MISO | GP12 | MISO pin of SPI |
| LCD_BL | GP13 | Backlight control |
| LCD_RST | GP15 | LCD reset pin, low active |
| TP_CS | GP16 | Touch select pin, low active |
| TP_IRQ | GP17 | Touch interrupt pin, low active |
| SDIO_CMD | GP18 | CMD pin of the SDIO interface |
| D0 | GP19 | D0 pin of the SDIO interface |
| D1 | GP20 | D1 pin of the SDIO interface |
| D2 | GP21 | D2 pin of the SDIO interface |
| SD_CS/D3 | GP22 | CS/D3 pin of the SDIO interface |
Setup environment
Please refer to Raspberry Pi's guide:https://www.raspberrypi.org/documentation/pico/getting-started/
Download Demo codes
Open terminal and run the following command：
wget -P ~/pico/ https://www.waveshare.net/w/upload/f/fc/Pico-ResTouch-LCD-X_X_Code.zip cd ~/pico unzip Pico-ResTouch-LCD-X_X_Code.zip
Run the Demo codes
This guides is based on Raspberry Pi.
C examples
- Hold the BOOTSEL button of Pico, then connect the USB port of Pico board to Raspberry Pi and then release the button
- Compile and run the c codes of Pico-ResTouch-LCD-X_X example
cd ~/pico/Pico-ResTouch-LCD-X_X_Code/c/build/ cmake .. make -j4 sudo mount /dev/sda1 /mnt/pico && sudo cp main.uf2 /mnt/pico/ && sudo sync && sudo umount /mnt/pico
- Run the codes in Pico, then the display will work
- You can press the RUN button of LCD for reseting pico. To enter disk mode, you can also first hold the BOOTSEL button and then the RUN button, then release the BOOTSEL button and then the RUN button without re-plug the pico
Python example
- Update the Thonny IDE if it doesn't support Pico
- Open the Thonny IDe and open the examples:
Codes Analysis
After running, this routine first displays some characters, patterns, and then displays pictures, and finally displays the touchpad function. C routine adaptes to PICO-RreTp=ouch-LD-2.8 and PICO-ResTouch-LD-3.5.In the main function, we place the three main functions in order and put the TP_DrawBoard(); Put in an endless loop to achieve the above functions
GUI_Show(); LCD_Show_bmp(Bmp_ScanDir , Lcd_ScanDir); TP_DrawBoard();
Before using LCD_SHOWBMP to display pictures, first copy the pictures in the PIC folder in the data to the SD Kagan directory, then insert the SD card into the SD card slot on the back of the screen and start downloading the program for testing
- Note that if the SD card is in FAT format, different pixel size images are required for different screens. 2.8-inch picture pixel size is 240×320, 3.5-inch picture pixel size is 480×320, and the image should be 24-bit deep color. BMP format
The display controller used in this product is ST77899(2.8inch)/ILI9488(3.5inch). We need to initialize this controller through the SPI communication protocol. The initialization functions are written in lcd_driv.c, which can be seen in the lcd_test.c file.
System_Init();//System initialization, configuration of serial port baud rate, SPI and related pins<br/>
LCD_SCAN_DIR Lcd_ScanDir = SCAN_DIR_DFT; //Setting scanning mode <br/> LCD_Init( Lcd_ScanDir, 200);//Initializes the screen and passes the scanning mode and backlight intensity<br/>
The function function about the screen display is written in LCD_GUI.c, the function of each function and the parameters passed are explained in the source code, need to use the direct call can be
- Draw point
void GUI_DrawPoint(POINT Xpoint, POINT Ypoint, COLOR Color,
DOT_PIXEL Dot_Pixel, DOT_STYLE DOT_STYLE)
- Draw line(dotted/solid)
void GUI_DrawLine(POINT Xstart, POINT Ystart, POINT Xend, POINT Yend,
COLOR Color, LINE_STYLE Line_Style, DOT_PIXEL Dot_Pixel)
- Draw rectange (empty/fulled)
void GUI_DrawRectangle(POINT Xstart, POINT Ystart, POINT Xend, POINT Yend,
COLOR Color, DRAW_FILL Filled, DOT_PIXEL Dot_Pixel)
- Draw circle (empty/Fulled)
void GUI_DrawCircle(POINT X_Center, POINT Y_Center, LENGTH Radius,
COLOR Color, DRAW_FILL Draw_Fill , DOT_PIXEL Dot_Pixel)
- Display character
void GUI_DisChar(POINT Xpoint, POINT Ypoint, const char Acsii_Char,
sFONT* Font, COLOR Color_Background, COLOR Color_Foreground)
- Dsiplay string
void GUI_DisString_EN(POINT Xstart, POINT Ystart, const char * pString,
sFONT* Font, COLOR Color_Background, COLOR Color_Foreground )
- Display number
void GUI_DisNum(POINT Xpoint, POINT Ypoint, int32_t Nummber,
sFONT* Font, COLOR Color_Background, COLOR Color_Foreground )
- Display time
void GUI_Showtime(POINT Xstart, POINT Ystart, POINT Xend, POINT Yend,
DEV_TIME *pTime, COLOR Color)
This routine shows BMP picture first is also through the SPI protocol to read the SD card BMP format picture data, and then the data to the image display
In the lcd_test.c file, the following two functions are used primarily to display images:
SD_Init();//Intialize SD card
LCD_Show_bmp(bmp_scan_dir,lcd_scan_dir);//Display BMP picture
These functions are written in LCD_Bmp. C, and actually read the image data in BMP format from the SD card with a specific file name and call our own display function to "express" the data as an image
In LCD_Touch.c file：
TP_Init( Lcd_ScanDir );//Touch pad initialization, pass parameters for scanning mode
TP_GetAdFac();//Calibrate touch pad
TP_Dialog();//Clear
TP_DrawBoard();//Begin the drawing board
After this routine runs, there are five colors on the right side of the screen. The system defaults to black. Touch to select a brush color. Click the AD button, click the red + sign according to the screen prompt to calibrate the screen; Click the upper right corner the CLEAR button to CLEAR the palette
The touch experiment uses four sets of calibration values by default, which can be used to handle brush operations in four directions. There are five color choices on the right, and the brush size is 9 pixels by default
The touchscreen functions are described in lcd_touch. c, and their function and the purpose of passing parameters are explained
Five fonts are provided in the codes:
Width 5，Height 8 font8 Width 7，Height 12 font12 Width 11，Height 16 font16 Width 14，Height 20 font20 Width 17，Height24 font24
- If you need characters of different sizes and fonts, you can use the font extraction software provided in the materials to create your own font library
- In fact you can also Image2Lcd [1] picture modulus software to convert images of different sizes different formats to array data, then use our written function display
If you require technical support, please go to the Support page and open a tickets.
