(Bonus 14) GD32L233 Review - Driving Segment Code LCD

韵湖葱白

(Bonus 14) GD32L233 Review - Driving Segment Code LCD [Copy link]

<i class="pstatus"> This post was last edited by Yunhu Congbai on 2022-4-29 08:59 </i> ## Preface I took a quick look at the information of GD32L233 before, and it supports SLCD driver, so I happily bought a bare screen; But later I took a closer look and found that CCT6 does not support it. The bare screen cannot be wasted, so I bought a Tianwei TM1621D driver and made an SLCD board myself. The board is actually quite simple, and the board is made as follows:  Among them: The R parameter in the signal pin RC parameter and the voltage divider resistor of VLCD can be directly referred to the manual. ## The principle of segment code LCD The most critical driving condition parameters are generally: - duty = 1/number of com - bias = 1/(sqrt(duty)+1)  SLCD executes the scanning mode according to the duty cycle, so simply understand: - SEG = address - COM = data--- If we need to display the first digit as 2, then the corresponding [8], where: label 2, label 3, label 4, label 6, label 7 will light up. Referring to the SEG diagram, we know: - SEG 9 corresponds to label 1, label 2, label 3, label 4, a total of 4 segments. - SEG 10 corresponds to 3 segments, namely, 5, 6 and 7 (we don't use the battery icon). If you want to light up 2, 3, 4, 6 and 7, then: - SEG 9: COM0 (4), COM1 (3) and COM2 (2) are 1. - SEG 10: COM2 (3) and COM3 (2) are 1. It is the following table: | | COM0 | COM1 | COM2 | COM3 | | --- | --- | --- | --- | --- | | SEG9 | 1 | 1 | 1 | 0 | | SEG10 | 0 | 0 | 1 | 1 | That is, writing 0xE and 0x3 to these two addresses will display the number 2. Do you understand? ！ ## The driver code has a bunch of register configurations, please refer to the chip manual. I was lazy and posted it here. [Note] The switching timing of SLCD is very short, so just use counting as the delay. ``` //#define SLCD_USING_SPI #if defined(SPI1_FOR_SLCD) /* SPI1:PB13-SCK-SPI_SCK PB14-CE-SPI_MISO PB15-DATA-SPI_MOSI */ #define CURRENT_SPI SPI1 #define CURRENT_SPI_RCU RCU_SPI1 #define SLCD_RCU RCU_GPIOB # SLCD_GPIO GPIOB #define SLCD_WR_CLK_PIN GPIO_PIN_13 #define SLCD_CS_PIN GPIO_PIN_14 #define SLCD_DATA_PIN GPIO_PIN_15 #ifdef SLCD_USING_SPI #else #define READ_MODE gpio_init_input_mode(RTC_RCU, SLCD_GPIO, RTC_DATA_PIN); ine WRITE_MODE gpio_init_output_mode(RTC_RCU, SLCD_GPIO, RTC_DATA_PIN, GPIO_OSPEED_50MHZ, 0); #define CS_HIGH gpio_bit_set(SLCD_GPIO, SLCD_CS_PIN); #define CS_LOW gpio_bit_reset(SLCD_GPIO, SLCD_CS_PIN); #define WR_CLK_HIGH gp io_bit_set(SLCD_GPIO, SLCD_WR_CLK_PIN); #define WR_CLK_LOW gpio_bit_reset(SLCD_GPIO, SLCD_WR_CLK_PIN); #define DATA_HIGH gpio_bit_set(SLCD_GPIO, SLCD_DATA_PIN); #define DATA_LOW gpio_bit_reset(SLCD_GPIO, SLCD_DATA_ PIN); #define DATA gpio_input_bit_get(SLCD_GPIO, SLCD_DATA_PIN) #endif // SLCD command code #define CTRL_CMD 0x80 //Write control command #define DATA_CMD 0xA0 //Write data command #define LCD_ON 0x06 //Turn on LCD 1000 0000 011x #define LCD_OFF 0x04 //Turn off LCD 1000 0000 010x #define SYS_EN 0x02 //System oscillator on 1000 0000 001x #define RC_OSC 0x30 //Internal RC oscillator (default 256K at power-on) 1000 0011 0XXX #define COM_BIAS 0x52 //4COM,1/3bias 1000 010 10X1X #define SLCD_OFF send_cmd_slcd(LCD_OFF) #define SLCD_ON send_cmd_slcd(LCD_ON) #define SLCD_SYS_EN send_cmd_slcd(SYS_EN) #define SLCD_RC_OSC send_cmd_slcd(RC_OSC) #define SLCD _COM_BIAS send_cmd_slcd(COM_BIAS) #define DISP_0 0xD7 #define DISP_1 0x06 # define DISP_2 0xE3 #define DISP_3 0xA7 #define DISP_4 0x36 #define DISP_5 0xB5 #define DISP_6 0xF5 #define DISP_7 0x07 #define DISP_8 0xF7 #define DISP_9 0xB7 #define DISP_A 0x77 #define DISP_B 0xF7 #define DISP_b 0xF4 #define DISP_C 0xD1 #define DISP_D 0xD7 #define DISP_c 0xE0 #define DISP_d 0xE6 #define DISP_E 0xF1 #define DISP_F 0x71 #define DISP_H 0x 76 #define DISP_h 0x74 #define DISP_L 0xD0 # define DISP_n 0x64 #define DISP_N 0x57 #define DISP_o 0xE4 #define DISP_P 0x73 #define DISP_r 0x60 #define DISP_t 0xF0 #define DISP_U 0xD6 #define DISP__ 0x20 #define DISP_EMPTY 0x00 void spi5_init(){} #ifdef SLCD_USING_SPI void spi1_init() { } #else void spi1_init() { gpio_init_output_mode(SLCD_RCU, SLCD_GPIO, SLCD_WR_CLK_PIN, GPIO_OSPEED_2MHZ, 0); output_mode(SLCD_RCU, SLCD_GPIO, SLCD_CS_PIN, GPIO_OSPEED_2MHZ, 0 ); gpio_init_output_mode(SLCD_RCU, SLCD_GPIO, SLCD_DATA_PIN, GPIO_OSPEED_50MHZ, 0); } static void slcd_delay(int count) { while (count) { count--; } } void send_bit_slcd(uint8_t sdat, uint8_t cnt) { //write the high cnt bit of data, the high bit comes first uint8_t i; for(i = 0; i < cnt; i++) { WR_CLK_LOW; slcd_delay(20); if(sdat&0x80) { DATA_HIGH; } else { DATA_LOW ; } slcd_delay(20); WR_CLK_HIGH; slcd_delay(20); sdat<<=1; } slcd_delay(20); } void send_cmd_slcd(uint8_t command) { //Send command CS_LOW; send_bit_slcd(CTRL_CMD, 4); //Write Enter the flag code b100 send_bit_slcd(command, 8); //There is no command with the highest bit as 1, directly write the highest bit of command to 0 CS_HIGH; } void write_slcd(uint8_t addr, uint8_t sdat) { addr<<=2; CS_LOW; send_bit_slcd(DATA_CMD, 3); //Write the flag code b101 send_bit_slcd(addr, 6); //Write the high 6 bits of addr send_bit_slcd(sdat , 8); //Write 8 bits of data CS_HIGH; } void slcd_user_init(void) { SLCD_OFF; SLCD_SYS_EN; SLCD_RC_OSC; SLCD_COM_BIAS; SLCD_ON; slcd_display_data(DISP_0,DISP_0,DISP_0,DISP_0,DISP_0,DISP_0);delay_ms(600) ; slcd_display_data(DISP_1,DISP_1,DISP_1,DISP_1,DISP_1,DISP_1);delay_ms(600); slcd_display_data(DISP_2,DISP_2,DISP_2,DISP_2,DISP_2,DISP_2);delay_ms(600); slcd_display_data(DISP_3,DISP_3,DI SP_3,DISP_3, DISP_3,DISP_3);delay_ms(600); slcd_display_data(DISP_4,DISP_4,DISP_4,DISP_4,DISP_4,DISP_4);delay_ms(600); slcd_display_data(DISP_5,DISP_5,DISP_5,DISP_5,DISP_5,DISP_5);delay_ms(600); slcd_display_data(DISP_6,DISP_6,DISP_6,DISP_6,DISP_6,DISP_6);delay_ms(600); slcd_display_data(DISP_7,DISP_7,DISP_7,DISP_7,DISP_7,DISP_7);delay_ms(600); slcd_display_data(DISP_8,DISP_8,DI SP_8,DISP_8, DISP_8,DISP_8);delay_ms(600); slcd_display_data(DISP_9,DISP_9,DISP_9,DISP_9,DISP_9,DISP_9);delay_ms(600); slcd_display_data(DISP__,DISP__,DISP__,DISP__,DISP__,DISP__);delay_ms(600); slcd_display_data( DISP_H,DISP_E,DISP_L,DISP_L,DISP_0,DISP_EMPTY); } void slcd_display_data(uint8_t data1, uint8_t data2, uint8_t data3, uint8_t data4, uint8_t data5, uint8_t data6) { uint8_t addr = 9; write_slcd(addr, data1); addr + = 2; write_slcd(addr, data2); addr += 2; write_slcd(addr, data3); addr += 2; write_slcd(addr, data4); addr += 2; write_slcd(addr, data5); addr += 2; write_slcd( addr, data6); addr += 2; } ``` ## Video 

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From design to program writing, if you have any ideas, you can learn from them. Thanks for sharing!