[Black Technology] a break electric lift tables, and transformed into the voice control (on) - Analog intermediaries to interact with the control handle

1, the circuit diagram decipher

The circuit board below, is a dedicated programmer control handle lift tables:

Simply look at the circuit board, which is a schematic guess 8 parallel and serial passage, for collecting the pressed key information; two strings turn 8 and drives the three 7-segment:

2, break the principle of its digital display

Thus a simple write a 74HC595 serial write data logic, respectively, to write display data observed (ESP8266 RTOS-based codes transformation from the GPIO DEMO):

#define GPIO_D4             2
#define GPIO_D5             14
#define GPIO_D6             12
#define GPIO_D7             13
#define GPIO_D8             15

#define GPIO_SCK            GPIO_D5   
#define GPIO_MISO           GPIO_D6
#define GPIO_MOSI           GPIO_D7
#define GPIO_NSS            GPIO_D4


#define GPIO_OUTPUT_PIN_SEL  ((1ULL<<GPIO_SCK) | (1ULL<<GPIO_MOSI) | (1ULL<<GPIO_NSS))
#define GPIO_INPUT_PIN_SEL  ((1ULL<<GPIO_MISO))


static void gpio_task_example(void *arg)
{
    int d = 0xFFDF;//待传输给74HC595的16bits数据
    int x = 0;
 
    while (1) {
        vTaskDelay(100 / portTICK_RATE_MS);
        gpio_set_level(GPIO_MOSI, (d>>x) & 0x01);//数据的一bit
        gpio_set_level(GPIO_SCK, 0);//SCK上升沿数据移入
        vTaskDelay(1 / portTICK_RATE_MS);
        gpio_set_level(GPIO_SCK, 1);

        x++;
        if(x == 16){//当所有16bits数据都送入了，NSS给一个上升沿，数据送到并口
            x=0;   
            gpio_set_level(GPIO_NSS, 0);
            vTaskDelay(1 / portTICK_RATE_MS);
            gpio_set_level(GPIO_NSS, 1);
        }
    }
}

void app_main(void)
{
    gpio_config_t io_conf;
    //disable interrupt
    io_conf.intr_type = GPIO_INTR_DISABLE;
    //set as output mode
    io_conf.mode = GPIO_MODE_OUTPUT;
    //bit mask of the pins that you want to set,e.g.GPIO15/16
    io_conf.pin_bit_mask = GPIO_OUTPUT_PIN_SEL;
    //disable pull-down mode
    io_conf.pull_down_en = 0;
    //disable pull-up mode
    io_conf.pull_up_en = 0;
    //configure GPIO with the given settings
    gpio_config(&io_conf);

    //bit mask of the pins, use GPIO4/5 here
    io_conf.pin_bit_mask = GPIO_INPUT_PIN_SEL;
    //set as input mode
    io_conf.mode = GPIO_MODE_INPUT;
    //enable pull-up mode
    io_conf.pull_up_en = 1;
    gpio_config(&io_conf);

    //start gpio task
    xTaskCreate(gpio_task_example, "gpio_task_example", 2048, NULL, 10, NULL);

    while (1) {
        vTaskDelay(1000000 / portTICK_RATE_MS);
    }
}

74HC595 which the principles of reference: https://blog.csdn.net/weixin_41445387/article/details/80500046
wherein the 3-digit 7-segment like this: ^{[# 2]}

3, let the digital display according to their wishes

Thus, the digital code corresponding to 0-9 as follows (16bits data is high 8bits):

digital	coding	Hex
0	1111 1100	0xFC
1	0110 0000	0x60
2	1101 1010	0xDA
3	1111 0010	0xF2
4	0110 0110	0x66
5	1011 0110	0xB6
6	1011 1110	0xBE
7	1110 0000	0xE0
8	1111 1110	0xFE
9	1111 0110	0xF6

Let the above figures 0-9 by 16bits at different sites in the low byte of the high 3bits implemented:

Place	coding
hundreds	xxxx xxxx 0010 0000
Ten	xxxx xxxx 0100 0000
Bit	xxxx xxxx 1000 0000

If you want to display a 3-digit number, is achieved by rapidly displaying a ten one hundred, the code is implemented as follows:

char digital[10] = {0xFC,0x60,0xDA,0xF2,0x66,0xB6,0xBE,0xE0,0xFE,0xF6};//0～9
char position[3] = {0x80,0x40,0x20};//百十个

void app_show_digital(int d){//显示1位数字
    for(int i=0;i<16;i++){
        gpio_set_level(GPIO_MOSI, (d>>i) & 0x01);
        gpio_set_level(GPIO_SCK, 0);
        gpio_set_level(GPIO_SCK, 1);
    }

    gpio_set_level(GPIO_NSS, 0);
    gpio_set_level(GPIO_NSS, 1);
}

void app_show_num(int num){//分时复用显示3位数字
    if(num < 0 || num > 999)return;

    static int show_pos = 0;
    int gsb[3];//个十百
    gsb[0] = digital[num%10];//个
    gsb[1] = digital[num/10%10];//十
    gsb[2] = digital[num/100];//百
    app_show_digital(gsb[show_pos] << 8 | position[show_pos]);

    show_pos++;
    if(show_pos == 3)show_pos = 0;
}

int show_num = 0;
static void gpio_task_example(void *arg)
{
    while (1) {
        app_show_num(show_num);
        vTaskDelay(9 / portTICK_RATE_MS);
    }
}

Note: Here it must be noted, in the make config, the RTOS frequency from 100Hz 200Hz transferred, otherwise the value of 10 or less (10 / portTICK_RATE_MS) vTaskDelay in all treated as 0, and can cause the system watchdog starve restart (watchdog timeout 26.1S also in config)

4, break their logical key operation

简单写一个74HC165串行读数据逻辑，用串口将读取的数据打印下来(代码基于ESP8266 RTOS的GPIO DEMO改造而来)：

char app_read_key(void){
    char data = 0;
    for(int i=0;i<8;i++){
        gpio_set_level(GPIO_SCK, 0);
        gpio_set_level(GPIO_SCK, 1);
        char bit = gpio_get_level(GPIO_MISO) == 0?0:1;
        data <<= 1;
        data |= bit;
    }
    return data;
}

int show_num = 0;
static void gpio_task_example(void *arg)
{
    while (1) {
        app_show_num(show_num);
        ESP_LOGI(TAG, "key: %X\n", app_read_key());
        vTaskDelay(9 / portTICK_RATE_MS);
    }
}

按动不同按键，看读取的数据：

按键	CODE	二进制
不按	7F	0111 1111
L1 上	7D	0111 1101
L2 下	7B	0111 1011
L3 一档	77	0111 0111
L4 二档	6F	0110 1111
L5 三档	5F	0101 1111
L6 四档	3F	0011 1111

: 小黑科技：将非智能升降桌改为智能升降桌
: 大家觉得不错，可以点推荐给更多人～

LINKS

[1]. 亮红色共阳0.36英寸3位数码管共阴红光3361AS/BS
[2]. 单片机芯片之——图解74HC595(第一部分)

@beautifulzzzz
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