Files
gobot/motor-control/firmware/src/tmc2209/uart_interface.cpp
2024-09-12 23:52:29 +02:00

80 lines
2.4 KiB
C++

#include "pico/stdlib.h"
#include "pico.h"
#include "hardware/uart.h"
#include "tmc2209.hpp"
TMC2209_UART::TMC2209_UART(
uart_inst_t *uart_inst,
uint8_t node_address,
uint baudrate,
uint tx_pin,
uint rx_pin
) {
this->uart_inst = uart_inst;
this->node_address = node_address & 0b11;
this->baudrate = baudrate;
this->tx_pin = tx_pin;
this->rx_pin = rx_pin;
}
void TMC2209_UART::init() {
gpio_set_function(this->tx_pin, UART_FUNCSEL_NUM(this->uart_inst, this->tx_pin));
gpio_set_function(this->rx_pin, UART_FUNCSEL_NUM(this->uart_inst, this->rx_pin));
// UART format: 8 data bits, 1 stop bit, no parity
// -> https://www.analog.com/media/en/technical-documentation/data-sheets/TMC2209_datasheet_rev1.09.pdf
uart_set_format(this->uart_inst, 8, 1, UART_PARITY_NONE);
// Clear to Send (CTS) and Request to Send (RTS) are not used
// (This is for automaticlly telling the other side that it is ready to receive/send data)
uart_set_hw_flow(this->uart_inst, false, false);
uart_set_fifo_enabled(this->uart_inst, true);
uart_init(this->uart_inst, this->baudrate);
}
uint8_t TMC2209_UART::calc_crc8_atm(uint8_t *data, uint8_t size) {
int i,j;
uint8_t crc = 0; // CRC located in last byte of message
uint8_t currentByte;
for (i=0; i<size; i++) { // Execute for all bytes of a message
currentByte = data[i]; // Retrieve a byte to be sent from Array
for (j=0; j<8; j++) {
if ((crc >> 7) ^ (currentByte & 0x01)) { // update CRC based result of XOR operation
crc = (crc << 1) ^ 0x07;
} else {
crc = (crc << 1);
}
currentByte = currentByte >> 1;
} // for CRC bit
} // for message byte
return crc;
}
uint32_t TMC2209_UART::read(uint8_t address) {
uint8_t data[4] = {
0b01010101, // Sync byte
this->node_address, // Node address
(address & (uint8_t)(0x7F)), // Register address, last bit is 0 for read
0
};
data[3] = this->calc_crc8_atm(data, 3);
uart_write_blocking(this->uart_inst, data, 4);
uint8_t response[12];
uart_read_blocking(this->uart_inst, response, 12);
if(response[11] != calc_crc8_atm(&response[4], 7)) {
this->crc_error_flag = true;
return 0;
} else {
return *((uint32_t*) &response[7]);
}
}