kopia lustrzana https://github.com/micropython/micropython
stmhal/machine_i2c: Provide HW implementation of I2C peripherals for F4.
With this patch machine.I2C() uses HW I2C peripheral blocks on F4 MCUs. Software I2C is used for other MCUs.pull/2654/head
rodzic
49dcc253e3
commit
f8b71aabb4
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@ -29,14 +29,398 @@
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#include "py/runtime.h"
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#include "py/mphal.h"
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#include "py/mperrno.h"
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#include "extmod/machine_i2c.h"
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#include "genhdr/pins.h"
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// for now we use the SW I2C implementation for the HW peripheral I2C blocks
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typedef mp_machine_soft_i2c_obj_t machine_hard_i2c_obj_t;
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#include "i2c.h"
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STATIC const mp_obj_type_t machine_hard_i2c_type;
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#if defined(MCU_SERIES_F4)
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// F4xx specific driver for I2C hardware peripheral
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// The hardware-specific I2C code below is based heavily on the code from
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// V1.5.2 of the STM32 CUBE F4 HAL. Its copyright notice is given here.
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/*
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* COPYRIGHT(c) 2016 STMicroelectronics
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*
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* Redistribution and use in source and binary forms, with or without modification,
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* are permitted provided that the following conditions are met:
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* 1. Redistributions of source code must retain the above copyright notice,
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* this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright notice,
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* this list of conditions and the following disclaimer in the documentation
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* and/or other materials provided with the distribution.
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* 3. Neither the name of STMicroelectronics nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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typedef struct _machine_hard_i2c_obj_t {
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mp_obj_base_t base;
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const pyb_i2c_obj_t *pyb;
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uint32_t *timeout;
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} machine_hard_i2c_obj_t;
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STATIC uint32_t machine_hard_i2c_timeout[4];
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STATIC const machine_hard_i2c_obj_t machine_hard_i2c_obj[] = {
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{{&machine_hard_i2c_type}, &pyb_i2c_obj[0], &machine_hard_i2c_timeout[0]},
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{{&machine_hard_i2c_type}, &pyb_i2c_obj[1], &machine_hard_i2c_timeout[1]},
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{{&machine_hard_i2c_type}, &pyb_i2c_obj[2], &machine_hard_i2c_timeout[2]},
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{{&machine_hard_i2c_type}, &pyb_i2c_obj[3], &machine_hard_i2c_timeout[3]},
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};
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STATIC void machine_hard_i2c_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
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machine_hard_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in);
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mp_printf(print, "I2C(%u, freq=%u, timeout=%u)",
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self - &machine_hard_i2c_obj[0] + 1,
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i2c_get_baudrate(&self->pyb->i2c->Init),
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*self->timeout);
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}
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STATIC void machine_hard_i2c_init(const machine_hard_i2c_obj_t *self, uint32_t freq, uint32_t timeout) {
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*self->timeout = timeout;
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i2c_init_freq(self->pyb, freq);
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}
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// this function is based on STM code
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STATIC bool I2C_IsAcknowledgeFailed(I2C_HandleTypeDef *hi2c) {
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if (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_AF) == SET) {
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/* Clear NACKF Flag */
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__HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_AF);
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return true;
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}
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return false;
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}
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// this function is based on STM code
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STATIC bool I2C_WaitOnFlagUntilTimeout(I2C_HandleTypeDef *hi2c, uint32_t Flag, FlagStatus Status, uint32_t Timeout, uint32_t Tickstart) {
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/* Wait until flag is set */
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while ((__HAL_I2C_GET_FLAG(hi2c, Flag) ? SET : RESET) == Status) {
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if (Timeout != HAL_MAX_DELAY) {
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if ((Timeout == 0U)||((HAL_GetTick() - Tickstart ) > Timeout)) {
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return false;
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}
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}
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}
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return true;
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}
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// this function is based on STM code
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STATIC int I2C_WaitOnRXNEFlagUntilTimeout(I2C_HandleTypeDef *hi2c, uint32_t Timeout, uint32_t Tickstart) {
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while (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_RXNE) == RESET) {
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/* Check if a STOPF is detected */
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if (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_STOPF) == SET) {
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/* Clear STOP Flag */
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__HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_STOPF);
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return -MP_EBUSY;
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}
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/* Check for the Timeout */
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if ((Timeout == 0U) || ((HAL_GetTick()-Tickstart) > Timeout)) {
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return -MP_ETIMEDOUT;
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}
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}
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return 0;
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}
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// this function is based on STM code
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STATIC int send_addr_byte(I2C_HandleTypeDef *hi2c, uint8_t addr_byte, uint32_t Timeout, uint32_t Tickstart) {
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/* Generate Start */
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hi2c->Instance->CR1 |= I2C_CR1_START;
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/* Wait until SB flag is set */
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if (!I2C_WaitOnFlagUntilTimeout(hi2c, I2C_FLAG_SB, RESET, Timeout, Tickstart)) {
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return -MP_ETIMEDOUT;
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}
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/* Send slave address */
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hi2c->Instance->DR = addr_byte;
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/* Wait until ADDR flag is set */
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while (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_ADDR) == RESET) {
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if (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_AF) == SET) {
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// nack received for addr, release the bus cleanly
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hi2c->Instance->CR1 |= I2C_CR1_STOP;
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__HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_AF);
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return -MP_ENODEV;
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}
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/* Check for the Timeout */
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if (Timeout != HAL_MAX_DELAY) {
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if ((Timeout == 0U)||((HAL_GetTick() - Tickstart ) > Timeout)) {
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return -MP_ETIMEDOUT;
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}
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}
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}
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return 0;
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}
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// this function is based on STM code
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int machine_hard_i2c_readfrom(mp_obj_base_t *self_in, uint16_t addr, uint8_t *dest, size_t len, bool stop) {
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machine_hard_i2c_obj_t *self = (machine_hard_i2c_obj_t*)self_in;
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I2C_HandleTypeDef *hi2c = self->pyb->i2c;
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uint32_t Timeout = *self->timeout;
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/* Init tickstart for timeout management*/
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uint32_t tickstart = HAL_GetTick();
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#if 0
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// TODO: for multi-master, here we could wait for the bus to be free
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// we'd need a flag to tell if we were in the middle of a set of transactions
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// (ie didn't send a stop bit in the last call)
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/* Wait until BUSY flag is reset */
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if (!I2C_WaitOnFlagUntilTimeout(hi2c, I2C_FLAG_BUSY, SET, I2C_TIMEOUT_BUSY_FLAG, tickstart)) {
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return -MP_EBUSY;
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}
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#endif
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/* Check if the I2C is already enabled */
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if ((hi2c->Instance->CR1 & I2C_CR1_PE) != I2C_CR1_PE) {
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/* Enable I2C peripheral */
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__HAL_I2C_ENABLE(hi2c);
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}
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/* Disable Pos */
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hi2c->Instance->CR1 &= ~I2C_CR1_POS;
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/* Enable Acknowledge */
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hi2c->Instance->CR1 |= I2C_CR1_ACK;
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/* Send Slave Address */
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int ret = send_addr_byte(hi2c, I2C_7BIT_ADD_READ(addr << 1), Timeout, tickstart);
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if (ret != 0) {
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return ret;
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}
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if (len == 0U) {
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/* Clear ADDR flag */
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__HAL_I2C_CLEAR_ADDRFLAG(hi2c);
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/* Generate Stop */
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if (stop) {
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hi2c->Instance->CR1 |= I2C_CR1_STOP;
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}
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} else if (len == 1U) {
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/* Disable Acknowledge */
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hi2c->Instance->CR1 &= ~I2C_CR1_ACK;
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/* Clear ADDR flag */
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__HAL_I2C_CLEAR_ADDRFLAG(hi2c);
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/* Generate Stop */
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if (stop) {
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hi2c->Instance->CR1 |= I2C_CR1_STOP;
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}
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} else if (len == 2U) {
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/* Disable Acknowledge */
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hi2c->Instance->CR1 &= ~I2C_CR1_ACK;
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/* Enable Pos */
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hi2c->Instance->CR1 |= I2C_CR1_POS;
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/* Clear ADDR flag */
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__HAL_I2C_CLEAR_ADDRFLAG(hi2c);
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} else {
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/* Enable Acknowledge */
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hi2c->Instance->CR1 |= I2C_CR1_ACK;
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/* Clear ADDR flag */
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__HAL_I2C_CLEAR_ADDRFLAG(hi2c);
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}
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while (len > 0U) {
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if (len <= 3U) {
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if (len == 1U) {
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/* Wait until RXNE flag is set */
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int ret = I2C_WaitOnRXNEFlagUntilTimeout(hi2c, Timeout, tickstart);
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if (ret != 0) {
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return ret;
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}
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/* Read data from DR */
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*dest++ = hi2c->Instance->DR;
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len--;
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} else if (len == 2U) {
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/* Wait until BTF flag is set */
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if (!I2C_WaitOnFlagUntilTimeout(hi2c, I2C_FLAG_BTF, RESET, Timeout, tickstart)) {
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return -MP_ETIMEDOUT;
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}
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/* Generate Stop */
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if (stop) {
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hi2c->Instance->CR1 |= I2C_CR1_STOP;
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}
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/* Read data from DR */
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*dest++ = hi2c->Instance->DR;
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len--;
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/* Read data from DR */
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*dest++ = hi2c->Instance->DR;
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len--;
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} else {
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/* Wait until BTF flag is set */
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if (!I2C_WaitOnFlagUntilTimeout(hi2c, I2C_FLAG_BTF, RESET, Timeout, tickstart)) {
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return -MP_ETIMEDOUT;
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}
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/* Disable Acknowledge */
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hi2c->Instance->CR1 &= ~I2C_CR1_ACK;
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/* Read data from DR */
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*dest++ = hi2c->Instance->DR;
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len--;
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/* Wait until BTF flag is set */
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if (!I2C_WaitOnFlagUntilTimeout(hi2c, I2C_FLAG_BTF, RESET, Timeout, tickstart)) {
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return -MP_ETIMEDOUT;
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}
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/* Generate Stop */
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if (stop) {
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hi2c->Instance->CR1 |= I2C_CR1_STOP;
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}
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/* Read data from DR */
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*dest++ = hi2c->Instance->DR;
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len--;
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/* Read data from DR */
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*dest++ = hi2c->Instance->DR;
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len--;
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}
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} else {
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/* Wait until RXNE flag is set */
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int ret = I2C_WaitOnRXNEFlagUntilTimeout(hi2c, Timeout, tickstart);
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if (ret != 0) {
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return ret;
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}
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/* Read data from DR */
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*dest++ = hi2c->Instance->DR;
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len--;
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if (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_BTF) == SET) {
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/* Read data from DR */
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*dest++ = hi2c->Instance->DR;
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len--;
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}
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}
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}
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return 0;
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}
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// this function is based on STM code
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int machine_hard_i2c_writeto(mp_obj_base_t *self_in, uint16_t addr, const uint8_t *src, size_t len, bool stop) {
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machine_hard_i2c_obj_t *self = (machine_hard_i2c_obj_t*)self_in;
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I2C_HandleTypeDef *hi2c = self->pyb->i2c;
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uint32_t Timeout = *self->timeout;
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/* Init tickstart for timeout management*/
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uint32_t tickstart = HAL_GetTick();
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#if 0
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// TODO: for multi-master, here we could wait for the bus to be free
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// we'd need a flag to tell if we were in the middle of a set of transactions
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// (ie didn't send a stop bit in the last call)
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/* Wait until BUSY flag is reset */
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if (!I2C_WaitOnFlagUntilTimeout(hi2c, I2C_FLAG_BUSY, SET, I2C_TIMEOUT_BUSY_FLAG, tickstart)) {
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return -MP_EBUSY;
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}
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#endif
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/* Check if the I2C is already enabled */
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if ((hi2c->Instance->CR1 & I2C_CR1_PE) != I2C_CR1_PE) {
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/* Enable I2C peripheral */
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__HAL_I2C_ENABLE(hi2c);
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}
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/* Disable Pos */
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hi2c->Instance->CR1 &= ~I2C_CR1_POS;
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/* Send Slave Address */
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int ret = send_addr_byte(hi2c, I2C_7BIT_ADD_WRITE(addr << 1), Timeout, tickstart);
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if (ret != 0) {
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return ret;
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}
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/* Clear ADDR flag */
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__HAL_I2C_CLEAR_ADDRFLAG(hi2c);
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int num_acks = 0;
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while (len > 0U) {
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/* Wait until TXE flag is set */
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while (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_TXE) == RESET) {
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/* Check if a NACK is detected */
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if (I2C_IsAcknowledgeFailed(hi2c)) {
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goto nack;
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}
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/* Check for the Timeout */
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if (Timeout != HAL_MAX_DELAY) {
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if ((Timeout == 0U) || ((HAL_GetTick()-tickstart) > Timeout)) {
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goto timeout;
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}
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}
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}
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/* Write data to DR */
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hi2c->Instance->DR = *src++;
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len--;
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/* Wait until BTF flag is set */
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while (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_BTF) == RESET) {
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/* Check if a NACK is detected */
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if (I2C_IsAcknowledgeFailed(hi2c)) {
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goto nack;
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}
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/* Check for the Timeout */
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if (Timeout != HAL_MAX_DELAY) {
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if ((Timeout == 0U) || ((HAL_GetTick()-tickstart) > Timeout)) {
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goto timeout;
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}
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}
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}
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++num_acks;
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}
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nack:
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/* Generate Stop */
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if (stop) {
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hi2c->Instance->CR1 |= I2C_CR1_STOP;
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}
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return num_acks;
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timeout:
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// timeout, release the bus cleanly
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hi2c->Instance->CR1 |= I2C_CR1_STOP;
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return -MP_ETIMEDOUT;
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}
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#else
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// No hardware I2C driver for this MCU so use the software implementation
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typedef mp_machine_soft_i2c_obj_t machine_hard_i2c_obj_t;
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STATIC machine_hard_i2c_obj_t machine_hard_i2c_obj[] = {
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#if defined(MICROPY_HW_I2C1_SCL)
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{{&machine_hard_i2c_type}, 1, 500, &MICROPY_HW_I2C1_SCL, &MICROPY_HW_I2C1_SDA},
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@ -53,6 +437,11 @@ STATIC machine_hard_i2c_obj_t machine_hard_i2c_obj[] = {
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#else
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{{NULL}, 0, 0, NULL, NULL},
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#endif
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#if defined(MICROPY_HW_I2C4_SCL)
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{{&machine_hard_i2c_type}, 1, 500, &MICROPY_HW_I2C4_SCL, &MICROPY_HW_I2C4_SDA},
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#else
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{{NULL}, 0, 0, NULL, NULL},
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#endif
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};
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STATIC void machine_hard_i2c_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
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|
@ -62,6 +451,33 @@ STATIC void machine_hard_i2c_print(const mp_print_t *print, mp_obj_t self_in, mp
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self->scl->name, self->sda->name, 500000 / self->us_delay, self->us_timeout);
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}
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STATIC void machine_hard_i2c_init(machine_hard_i2c_obj_t *self, uint32_t freq, uint32_t timeout) {
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// set parameters
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if (freq >= 1000000) {
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// allow fastest possible bit-bang rate
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self->us_delay = 0;
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} else {
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self->us_delay = 500000 / freq;
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if (self->us_delay == 0) {
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self->us_delay = 1;
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}
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}
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self->us_timeout = timeout;
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// init pins
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mp_hal_pin_open_drain(self->scl);
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mp_hal_pin_open_drain(self->sda);
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}
|
||||
|
||||
#define machine_hard_i2c_readfrom mp_machine_soft_i2c_readfrom
|
||||
#define machine_hard_i2c_writeto mp_machine_soft_i2c_writeto
|
||||
|
||||
#endif
|
||||
|
||||
/******************************************************************************/
|
||||
/* MicroPython bindings for machine API */
|
||||
|
||||
mp_obj_t machine_hard_i2c_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
|
||||
// parse args
|
||||
enum { ARG_id, ARG_scl, ARG_sda, ARG_freq, ARG_timeout };
|
||||
|
@ -69,8 +485,8 @@ mp_obj_t machine_hard_i2c_make_new(const mp_obj_type_t *type, size_t n_args, siz
|
|||
{ MP_QSTR_id, MP_ARG_REQUIRED | MP_ARG_OBJ },
|
||||
{ MP_QSTR_scl, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
|
||||
{ MP_QSTR_sda, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
|
||||
{ MP_QSTR_freq, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
|
||||
{ MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
|
||||
{ MP_QSTR_freq, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 400000} },
|
||||
{ MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 1000} },
|
||||
};
|
||||
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
|
||||
mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
|
||||
|
@ -106,39 +522,22 @@ mp_obj_t machine_hard_i2c_make_new(const mp_obj_type_t *type, size_t n_args, siz
|
|||
}
|
||||
|
||||
// get static peripheral object
|
||||
machine_hard_i2c_obj_t *self = &machine_hard_i2c_obj[i2c_id - 1];
|
||||
machine_hard_i2c_obj_t *self = (machine_hard_i2c_obj_t*)&machine_hard_i2c_obj[i2c_id - 1];
|
||||
|
||||
// here we would check the scl/sda pins and configure them, but it's not implemented
|
||||
if (args[ARG_scl].u_obj != MP_OBJ_NULL || args[ARG_sda].u_obj != MP_OBJ_NULL) {
|
||||
mp_raise_ValueError("explicit choice of scl/sda is not implemented");
|
||||
}
|
||||
|
||||
// set parameters
|
||||
if (args[ARG_freq].u_int != -1) {
|
||||
if (args[ARG_freq].u_int >= 1000000) {
|
||||
// allow fastest possible bit-bang rate
|
||||
self->us_delay = 0;
|
||||
} else {
|
||||
self->us_delay = 500000 / args[ARG_freq].u_int;
|
||||
if (self->us_delay == 0) {
|
||||
self->us_delay = 1;
|
||||
}
|
||||
}
|
||||
}
|
||||
if (args[ARG_timeout].u_int != -1) {
|
||||
self->us_timeout = args[ARG_timeout].u_int;
|
||||
}
|
||||
|
||||
// init pins
|
||||
mp_hal_pin_open_drain(self->scl);
|
||||
mp_hal_pin_open_drain(self->sda);
|
||||
// initialise the I2C peripheral
|
||||
machine_hard_i2c_init(self, args[ARG_freq].u_int, args[ARG_timeout].u_int);
|
||||
|
||||
return MP_OBJ_FROM_PTR(self);
|
||||
}
|
||||
|
||||
STATIC const mp_machine_i2c_p_t machine_hard_i2c_p = {
|
||||
.readfrom = mp_machine_soft_i2c_readfrom,
|
||||
.writeto = mp_machine_soft_i2c_writeto,
|
||||
.readfrom = machine_hard_i2c_readfrom,
|
||||
.writeto = machine_hard_i2c_writeto,
|
||||
};
|
||||
|
||||
STATIC const mp_obj_type_t machine_hard_i2c_type = {
|
||||
|
|
Ładowanie…
Reference in New Issue