circuitpython/nrf5/hal/hal_twi.c

134 lines
4.1 KiB
C
Raw Normal View History

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2017 Glenn Ruben Bakke
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "mphalport.h"
#include "hal_twi.h"
#ifdef HAL_TWI_MODULE_ENABLED
static const uint32_t hal_twi_frequency_lookup[] = {
TWI_FREQUENCY_FREQUENCY_K100, // 100 kbps
TWI_FREQUENCY_FREQUENCY_K250, // 250 kbps
TWI_FREQUENCY_FREQUENCY_K400, // 400 kbps
};
void hal_twi_master_init(NRF_TWI_Type * p_instance, hal_twi_init_t const * p_twi_init) {
#if NRF52840_XXAA
p_instance->PSEL.SCL = p_twi_init->scl_pin->pin;
p_instance->PSEL.SDA = p_twi_init->sda_pin->pin;
p_instance->PSEL.SCL |= (p_twi_init->scl_pin->port << TWI_PSEL_SCL_PORT_Pos);
p_instance->PSEL.SDA |= (p_twi_init->sda_pin->port << TWI_PSEL_SDA_PORT_Pos);
#else
p_instance->PSELSCL = p_twi_init->scl_pin->pin;
p_instance->PSELSDA = p_twi_init->sda_pin->pin;
#endif
p_instance->FREQUENCY = hal_twi_frequency_lookup[p_twi_init->freq];
p_instance->ENABLE = (TWI_ENABLE_ENABLE_Enabled << TWI_ENABLE_ENABLE_Pos);
}
#include <stdio.h>
void hal_twi_master_tx(NRF_TWI_Type * p_instance,
uint8_t addr,
uint16_t transfer_size,
const uint8_t * tx_data,
bool stop) {
uint16_t number_of_txd_bytes = 0;
p_instance->ADDRESS = addr;
p_instance->EVENTS_TXDSENT = 0;
p_instance->TXD = tx_data[number_of_txd_bytes];
p_instance->TASKS_STARTTX = 1;
while (number_of_txd_bytes < transfer_size) {
// wait for the transaction complete
while (p_instance->EVENTS_TXDSENT == 0) {
;
}
number_of_txd_bytes++;
// TODO: This could go one byte out of bound.
p_instance->TXD = tx_data[number_of_txd_bytes];
p_instance->EVENTS_TXDSENT = 0;
}
if (stop) {
p_instance->EVENTS_STOPPED = 0;
p_instance->TASKS_STOP = 1;
while (p_instance->EVENTS_STOPPED == 0) {
;
}
}
}
void hal_twi_master_rx(NRF_TWI_Type * p_instance,
uint8_t addr,
uint16_t transfer_size,
uint8_t * rx_data,
bool stop) {
uint16_t number_of_rxd_bytes = 0;
p_instance->ADDRESS = addr;
p_instance->EVENTS_RXDREADY = 0;
p_instance->TASKS_STARTRX = 1;
while (number_of_rxd_bytes < transfer_size) {
// wait for the transaction complete
while (p_instance->EVENTS_RXDREADY == 0) {
;
}
rx_data[number_of_rxd_bytes] = p_instance->RXD;
p_instance->EVENTS_RXDREADY = 0;
number_of_rxd_bytes++;
}
if (stop) {
p_instance->EVENTS_STOPPED = 0;
p_instance->TASKS_STOP = 1;
while (p_instance->EVENTS_STOPPED == 0) {
;
}
}
}
void hal_twi_slave_init(NRF_TWI_Type * p_instance, hal_twi_init_t const * p_twi_init) {
}
#endif // HAL_TWI_MODULE_ENABLED