Files
esphome-lsm6ds/esphome/components/mcp23s17/mcp23s17.cpp
T

84 lines
2.4 KiB
C++

#include "mcp23s17.h"
#include "esphome/core/log.h"
namespace esphome {
namespace mcp23s17 {
static const char *const TAG = "mcp23s17";
// IOCON register bits
static constexpr uint8_t IOCON_SEQOP = 0x20; // Sequential operation mode
static constexpr uint8_t IOCON_MIRROR = 0x40; // Mirror INTA/INTB pins
static constexpr uint8_t IOCON_HAEN = 0x08; // Hardware address enable
static constexpr uint8_t IOCON_ODR = 0x04; // Open-drain output for INT pin
void MCP23S17::set_device_address(uint8_t device_addr) {
if (device_addr != 0) {
this->device_opcode_ |= ((device_addr & 0b111) << 1);
}
}
void MCP23S17::setup() {
this->spi_setup();
// Enable HAEN (broadcast to addresses 0 and 4 since HAEN isn't active yet)
this->enable();
this->transfer_byte(0b01000000);
this->transfer_byte(mcp23x17_base::MCP23X17_IOCONA);
this->transfer_byte(IOCON_SEQOP | IOCON_HAEN);
this->disable();
this->enable();
this->transfer_byte(0b01001000);
this->transfer_byte(mcp23x17_base::MCP23X17_IOCONA);
this->transfer_byte(IOCON_SEQOP | IOCON_HAEN);
this->disable();
// Read current output register state
this->read_reg(mcp23x17_base::MCP23X17_OLATA, &this->olat_a_);
this->read_reg(mcp23x17_base::MCP23X17_OLATB, &this->olat_b_);
uint8_t iocon_flags = IOCON_SEQOP | IOCON_HAEN;
if (this->open_drain_ints_) {
iocon_flags |= IOCON_ODR;
}
if (this->interrupt_pin_ != nullptr) {
// Mirror INTA/INTB so either pin fires for changes on any port
iocon_flags |= IOCON_MIRROR;
}
if (this->open_drain_ints_ || this->interrupt_pin_ != nullptr) {
this->write_reg(mcp23x17_base::MCP23X17_IOCONA, iocon_flags);
this->write_reg(mcp23x17_base::MCP23X17_IOCONB, iocon_flags);
}
this->setup_interrupt_pin_();
}
void MCP23S17::dump_config() {
ESP_LOGCONFIG(TAG, "MCP23S17:");
LOG_PIN(" CS Pin: ", this->cs_);
LOG_PIN(" Interrupt Pin: ", this->interrupt_pin_);
}
bool MCP23S17::read_reg(uint8_t reg, uint8_t *value) {
this->enable();
this->transfer_byte(this->device_opcode_ | 1);
this->transfer_byte(reg);
*value = this->transfer_byte(0xFF);
this->disable();
return true;
}
bool MCP23S17::write_reg(uint8_t reg, uint8_t value) {
this->enable();
this->transfer_byte(this->device_opcode_);
this->transfer_byte(reg);
this->transfer_byte(value);
this->disable();
return true;
}
} // namespace mcp23s17
} // namespace esphome