有很多方法可以做到这一点。我经常一个接一个地做。
一种简单的方法是通过定义一个变量来制作自己的“注册”。如果寄存器是 8 位宽,定义字节变量:
unsigned char disp_register;
然后你写入这个寄存器,就像它存在于显示硬件中一样。当然,接下来你必须将此寄存器输出到 ESP32 的 GPIO 引脚。由于引脚都已完成,因此您必须逐个引脚执行此操作。定义您的硬件引脚以提高可读性:
/* OUTPUTS (numbers mean GPIO port) */
#define REGISTER_BIT7_ON_PIN 9
#define REGISTER_BIT6_ON_PIN 10
#define REGISTER_BIT5_ON_PIN 5
// continue with all the pins you need
在程序开始的某个地方,将这些引脚设置为输出,并可能将它们的默认值设置为“0”:
io_conf.intr_type = GPIO_PIN_INTR_DISABLE;
io_conf.mode = GPIO_MODE_OUTPUT;
io_conf.pull_down_en = GPIO_PULLDOWN_DISABLE;
io_conf.pull_up_en = GPIO_PULLUP_DISABLE;
io_conf.pin_bit_mask = ((1ULL<< REGISTER_BIT7_ON_PIN) | (1ULL<< REGISTER_BIT6_ON_PIN) | (1ULL<< REGISTER_BIT5_ON_PIN)); // of course, do like this all the pins
gpio_config(&io_conf);
gpio_set_level(REGISTER_BIT7_ON_PIN, 0); // do like this all the pins you need to set the boot-up value, pin-by-pin
接下来,您需要您的函数将您的寄存器复制到 GPIO 引脚的外部世界:
/*
* wrote this simply for ease of understanding, feel free to do this in a loop
* or shifting bit by bit
*/
void copy_register_to_GPIO_pins(unsigned char disp_register)
{
gpio_set_level(REGISTER_BIT7_ON_PIN, (disp_register & 0x80) >> 7);
gpio_set_level(REGISTER_BIT6_ON_PIN, (disp_register & 0x40) >> 6);
gpio_set_level(REGISTER_BIT5_ON_PIN, (disp_register & 0x20) >> 5);
gpio_set_level(REGISTER_BIT4_ON_PIN, (disp_register & 0x10) >> 4);
gpio_set_level(REGISTER_BIT3_ON_PIN, (disp_register & 0x08) >> 3);
gpio_set_level(REGISTER_BIT2_ON_PIN, (disp_register & 0x04) >> 2);
gpio_set_level(REGISTER_BIT1_ON_PIN, (disp_register & 0x02) >> 1);
gpio_set_level(REGISTER_BIT0_ON_PIN, (disp_register & 0x01));
}
然后,在您将任何内容写入寄存器后,调用您的函数以输出它:
disp_register = 0x2A; // example value you want to send to display
copy_register_to_GPIO_pins(disp_register);
// or, output byte WITHOUT using any register:
copy_register_to_GPIO_pins(0x2A);
希望您可以自己做相反的事情,读取引脚是由另一个函数完成的,您可以在其中复制每个 GPIO 引脚值并将其组装成字节变量。当然,此时必须将引脚设置为输入。原则上:
/*
* wrote this simply for ease of understanding
*/
unsigned char copy_GPIO_pins_to_register(void)
{
unsigned char retval = 0;
retval |= gpio_get_level(REGISTER_BIT7_ON_PIN);
retval = retval << 1;
retval |= gpio_get_level(REGISTER_BIT6_ON_PIN);
retval = retval << 1;
retval |= gpio_get_level(REGISTER_BIT5_ON_PIN);
retval = retval << 1;
retval |= gpio_get_level(REGISTER_BIT4_ON_PIN);
retval = retval << 1;
retval |= gpio_get_level(REGISTER_BIT3_ON_PIN);
retval = retval << 1;
retval |= gpio_get_level(REGISTER_BIT2_ON_PIN);
retval = retval << 1;
retval |= gpio_get_level(REGISTER_BIT1_ON_PIN);
retval = retval << 1;
retval |= gpio_get_level(REGISTER_BIT0_ON_PIN);
return retval;
}