sn74hc165.cpp

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#include "sn74hc165.h"
#include "esphome/core/log.h"
 
namespace esphome {
namespace sn74hc165 {
 
static const char *const TAG = "sn74hc165";
 
void SN74HC165Component::setup() {
  // initialize pins
  this->clock_pin_->setup();
  this->data_pin_->setup();
  this->load_pin_->setup();
  this->clock_pin_->digital_write(false);
  this->load_pin_->digital_write(false);
 
  if (this->clock_inhibit_pin_ != nullptr) {
    this->clock_inhibit_pin_->setup();
    this->clock_inhibit_pin_->digital_write(true);
  }
 
  // read state from shift register
  this->read_gpio_();
}
 
void SN74HC165Component::loop() { this->read_gpio_(); }
 
void SN74HC165Component::dump_config() { ESP_LOGCONFIG(TAG, "SN74HC165:"); }
 
bool SN74HC165Component::digital_read_(uint16_t pin) {
  if (pin >= this->sr_count_ * 8) {
    ESP_LOGE(TAG, "Pin %u is out of range! Maximum pin number with %u chips in series is %u", pin, this->sr_count_,
             (this->sr_count_ * 8) - 1);
    return false;
  }
  return this->input_bits_[pin];
}
 
void SN74HC165Component::read_gpio_() {
  this->load_pin_->digital_write(false);
  delayMicroseconds(10);
  this->load_pin_->digital_write(true);
  delayMicroseconds(10);
 
  if (this->clock_inhibit_pin_ != nullptr)
    this->clock_inhibit_pin_->digital_write(false);
 
  for (uint8_t i = 0; i < this->sr_count_; i++) {
    for (uint8_t j = 0; j < 8; j++) {
      this->input_bits_[(i * 8) + (7 - j)] = this->data_pin_->digital_read();
 
      this->clock_pin_->digital_write(true);
      delayMicroseconds(10);
      this->clock_pin_->digital_write(false);
      delayMicroseconds(10);
    }
  }
 
  if (this->clock_inhibit_pin_ != nullptr)
    this->clock_inhibit_pin_->digital_write(true);
}
 
float SN74HC165Component::get_setup_priority() const { return setup_priority::IO; }
 
bool SN74HC165GPIOPin::digital_read() { return this->parent_->digital_read_(this->pin_) != this->inverted_; }
 
std::string SN74HC165GPIOPin::dump_summary() const { return str_snprintf("%u via SN74HC165", 18, pin_); }
 
}  // namespace sn74hc165
}  // namespace esphome