English Character Display Principle

let's learn how ASCII codes are displayed. The following takes the STM32 program of the 2.13-inch e-Paper HAT as an example to explain. To display characters, you must need fonts first. The files of the Fonts directory in the sample program correspond to different fonts. Open the file and you can see a bunch of data.

Each font has a structure that stores information about the font respectively. The structure includes an array pointer, font width, and font height.

The above fonts are copied from the stm32 official sample program. It is an ASCII character. Now let's explain how we make the font. The picture below is the font modulo of the "A" of Font8, we can use the font modulo software to get the data of the A character.

Related software Zimo221

The font data can be got from the font modulo software which extracts the modulo of the font horizontally and vertically and displays each pixel with an array. For instance, if you want to display the "A" character, you can find the data of the "A" character and then display the font modulo point by point.

One thing to note here is the red box, the font array is stored in ASCII order, the first character is a space " ", and the data size of each character is the same. So subtract the ASCII code of the space bar from the ASCII code of A to find the starting position of the data for the character "A".

String display is to display each character.

TAG： ESP32 Portable Pendant Serial UART Bus Servo CF35-12 TTL 35KG.CM Magnetic-Encoder High precision and Large torque Raspberry Pi Pico 2 RP2350B 2.8 inch LCD Development Board RGB Display Round TouchScreen 480x480 LVGL QMI8658 / SD / RTC ESP32 S3 Development Board 1.85 inch Round LCD Display 360&amp;amp;times;360 QMI8658 Sensor / MIC / SD /MP3 Audio /Battery Port LVGL/HMI For Arduino Raspberry Pi LCD Capacitive TouchScreen Display HDMI 6.25inch 720x1560 14 inch Dual LCD Computer PC Monitor Display Double Secondary Screen Type C Mini HDMI 1080P For Windows/MacOS Raspberry Pi 5 PCIe to USB Gen1 HUB and M.2 NVMe SSD PI5 Expansion board HAT+ PC USB Secondary Screen RK3566 Arduino-check-library-path Raspberry Pi LCD Raspberry Pi RP2040 Raspberry Pi 5 TOF Time of Flight Laser Range Sensor Mini Radar module UART Serial / I2C Port For Arduino / Raspberry Pi / ESP32 X1009 Raspberry Pi 5 PCIe To 5-Port SATA SATA3.0 (NOT BOOT From SATA) Electronic EYE 0.71 inch Round Double LCD Display Dual Screen For Arduino Raspberry Pi ESP32 Pico ST FLASH File System Operation PC Secondary Screen Raspberry Pi 5 Fan Sipeed Tang Primer 25K GW5A RISCV FPGA Development Board Dock SDRAM GW5A-LV25MG121 Retro Game linux

English Character Display Principle

VS1003 module MP3 player audio decoding development board onboard recording function

[Tutorial Navigation]