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circuitpython/stmhal/spi.c
Damien George b932b2dd1f extmod/machine_spi: Use delay_half, not baudrate, for internal timing. 
The delay_half parameter must be specified by the port to set up the
timing of the software SPI.  This allows the port to adjust the timing
value to better suit its timing characteristics, as well as provide a
more accurate printing of the baudrate.
2016-10-04 13:43:02 +11:00

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/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
*
* 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 <stdio.h>
#include <string.h>
#include "py/nlr.h"
#include "py/runtime.h"
#include "py/mphal.h"
#include "extmod/machine_spi.h"
#include "irq.h"
#include "pin.h"
#include "genhdr/pins.h"
#include "bufhelper.h"
#include "dma.h"
#include "spi.h"
/// \moduleref pyb
/// \class SPI - a master-driven serial protocol
///
/// SPI is a serial protocol that is driven by a master. At the physical level
/// there are 3 lines: SCK, MOSI, MISO.
///
/// See usage model of I2C; SPI is very similar. Main difference is
/// parameters to init the SPI bus:
///
/// from pyb import SPI
/// spi = SPI(1, SPI.MASTER, baudrate=600000, polarity=1, phase=0, crc=0x7)
///
/// Only required parameter is mode, SPI.MASTER or SPI.SLAVE. Polarity can be
/// 0 or 1, and is the level the idle clock line sits at. Phase can be 0 or 1
/// to sample data on the first or second clock edge respectively. Crc can be
/// None for no CRC, or a polynomial specifier.
///
/// Additional method for SPI:
///
/// data = spi.send_recv(b'1234') # send 4 bytes and receive 4 bytes
/// buf = bytearray(4)
/// spi.send_recv(b'1234', buf) # send 4 bytes and receive 4 into buf
/// spi.send_recv(buf, buf) # send/recv 4 bytes from/to buf
// Possible DMA configurations for SPI busses:
// SPI1_TX: DMA2_Stream3.CHANNEL_3 or DMA2_Stream5.CHANNEL_3
// SPI1_RX: DMA2_Stream0.CHANNEL_3 or DMA2_Stream2.CHANNEL_3
// SPI2_TX: DMA1_Stream4.CHANNEL_0
// SPI2_RX: DMA1_Stream3.CHANNEL_0
// SPI3_TX: DMA1_Stream5.CHANNEL_0 or DMA1_Stream7.CHANNEL_0
// SPI3_RX: DMA1_Stream0.CHANNEL_0 or DMA1_Stream2.CHANNEL_0
// SPI4_TX: DMA2_Stream4.CHANNEL_5 or DMA2_Stream1.CHANNEL_4
// SPI4_RX: DMA2_Stream3.CHANNEL_5 or DMA2_Stream0.CHANNEL_4
// SPI5_TX: DMA2_Stream4.CHANNEL_2 or DMA2_Stream6.CHANNEL_7
// SPI5_RX: DMA2_Stream3.CHANNEL_2 or DMA2_Stream5.CHANNEL_7
// SPI6_TX: DMA2_Stream5.CHANNEL_1
// SPI6_RX: DMA2_Stream6.CHANNEL_1
typedef struct _pyb_spi_obj_t {
mp_obj_base_t base;
SPI_HandleTypeDef *spi;
const dma_descr_t *tx_dma_descr;
const dma_descr_t *rx_dma_descr;
} pyb_spi_obj_t;
#if defined(MICROPY_HW_SPI1_SCK)
SPI_HandleTypeDef SPIHandle1 = {.Instance = NULL};
#endif
#if defined(MICROPY_HW_SPI2_SCK)
SPI_HandleTypeDef SPIHandle2 = {.Instance = NULL};
#endif
#if defined(MICROPY_HW_SPI3_SCK)
SPI_HandleTypeDef SPIHandle3 = {.Instance = NULL};
#endif
#if defined(MICROPY_HW_SPI4_SCK)
SPI_HandleTypeDef SPIHandle4 = {.Instance = NULL};
#endif
#if defined(MICROPY_HW_SPI5_SCK)
SPI_HandleTypeDef SPIHandle5 = {.Instance = NULL};
#endif
#if defined(MICROPY_HW_SPI6_SCK)
SPI_HandleTypeDef SPIHandle6 = {.Instance = NULL};
#endif
STATIC const pyb_spi_obj_t pyb_spi_obj[] = {
#if defined(MICROPY_HW_SPI1_SCK)
{{&pyb_spi_type}, &SPIHandle1, &dma_SPI_1_TX, &dma_SPI_1_RX},
#else
{{&pyb_spi_type}, NULL, NULL, NULL},
#endif
#if defined(MICROPY_HW_SPI2_SCK)
{{&pyb_spi_type}, &SPIHandle2, &dma_SPI_2_TX, &dma_SPI_2_RX},
#else
{{&pyb_spi_type}, NULL, NULL, NULL},
#endif
#if defined(MICROPY_HW_SPI3_SCK)
{{&pyb_spi_type}, &SPIHandle3, &dma_SPI_3_TX, &dma_SPI_3_RX},
#else
{{&pyb_spi_type}, NULL, NULL, NULL},
#endif
#if defined(MICROPY_HW_SPI4_SCK)
{{&pyb_spi_type}, &SPIHandle4, &dma_SPI_4_TX, &dma_SPI_4_RX},
#else
{{&pyb_spi_type}, NULL, NULL, NULL},
#endif
#if defined(MICROPY_HW_SPI5_SCK)
{{&pyb_spi_type}, &SPIHandle5, &dma_SPI_5_TX, &dma_SPI_5_RX},
#else
{{&pyb_spi_type}, NULL, NULL, NULL},
#endif
#if defined(MICROPY_HW_SPI6_SCK)
{{&pyb_spi_type}, &SPIHandle6, &dma_SPI_6_TX, &dma_SPI_6_RX},
#else
{{&pyb_spi_type}, NULL, NULL, NULL},
#endif
};
void spi_init0(void) {
// reset the SPI handles
#if defined(MICROPY_HW_SPI1_SCK)
memset(&SPIHandle1, 0, sizeof(SPI_HandleTypeDef));
SPIHandle1.Instance = SPI1;
#endif
#if defined(MICROPY_HW_SPI2_SCK)
memset(&SPIHandle2, 0, sizeof(SPI_HandleTypeDef));
SPIHandle2.Instance = SPI2;
#endif
#if defined(MICROPY_HW_SPI3_SCK)
memset(&SPIHandle3, 0, sizeof(SPI_HandleTypeDef));
SPIHandle3.Instance = SPI3;
#endif
#if defined(MICROPY_HW_SPI4_SCK)
memset(&SPIHandle4, 0, sizeof(SPI_HandleTypeDef));
SPIHandle4.Instance = SPI4;
#endif
#if defined(MICROPY_HW_SPI5_SCK)
memset(&SPIHandle5, 0, sizeof(SPI_HandleTypeDef));
SPIHandle5.Instance = SPI5;
#endif
#if defined(MICROPY_HW_SPI6_SCK)
memset(&SPIHandle6, 0, sizeof(SPI_HandleTypeDef));
SPIHandle6.Instance = SPI6;
#endif
}
STATIC int spi_find(mp_obj_t id) {
if (MP_OBJ_IS_STR(id)) {
// given a string id
const char *port = mp_obj_str_get_str(id);
if (0) {
#ifdef MICROPY_HW_SPI1_NAME
} else if (strcmp(port, MICROPY_HW_SPI1_NAME) == 0) {
return 1;
#endif
#ifdef MICROPY_HW_SPI2_NAME
} else if (strcmp(port, MICROPY_HW_SPI2_NAME) == 0) {
return 2;
#endif
#ifdef MICROPY_HW_SPI3_NAME
} else if (strcmp(port, MICROPY_HW_SPI3_NAME) == 0) {
return 3;
#endif
}
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError,
"SPI(%s) does not exist", port));
} else {
// given an integer id
int spi_id = mp_obj_get_int(id);
if (spi_id >= 1 && spi_id <= MP_ARRAY_SIZE(pyb_spi_obj)
&& pyb_spi_obj[spi_id - 1].spi != NULL) {
return spi_id;
}
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError,
"SPI(%d) does not exist", spi_id));
}
}
// sets the parameters in the SPI_InitTypeDef struct
// if an argument is -1 then the corresponding parameter is not changed
STATIC void spi_set_params(SPI_HandleTypeDef *spi, uint32_t prescale, int32_t baudrate,
int32_t polarity, int32_t phase, int32_t bits, int32_t firstbit) {
SPI_InitTypeDef *init = &spi->Init;
if (prescale != 0xffffffff || baudrate != -1) {
if (prescale == 0xffffffff) {
// prescaler not given, so select one that yields at most the requested baudrate
mp_uint_t spi_clock;
if (spi->Instance == SPI2 || spi->Instance == SPI3) {
// SPI2 and SPI3 are on APB1
spi_clock = HAL_RCC_GetPCLK1Freq();
} else {
// SPI1, SPI4, SPI5 and SPI6 are on APB2
spi_clock = HAL_RCC_GetPCLK2Freq();
}
prescale = spi_clock / baudrate;
}
if (prescale <= 2) { init->BaudRatePrescaler = SPI_BAUDRATEPRESCALER_2; }
else if (prescale <= 4) { init->BaudRatePrescaler = SPI_BAUDRATEPRESCALER_4; }
else if (prescale <= 8) { init->BaudRatePrescaler = SPI_BAUDRATEPRESCALER_8; }
else if (prescale <= 16) { init->BaudRatePrescaler = SPI_BAUDRATEPRESCALER_16; }
else if (prescale <= 32) { init->BaudRatePrescaler = SPI_BAUDRATEPRESCALER_32; }
else if (prescale <= 64) { init->BaudRatePrescaler = SPI_BAUDRATEPRESCALER_64; }
else if (prescale <= 128) { init->BaudRatePrescaler = SPI_BAUDRATEPRESCALER_128; }
else { init->BaudRatePrescaler = SPI_BAUDRATEPRESCALER_256; }
}
if (polarity != -1) {
init->CLKPolarity = polarity == 0 ? SPI_POLARITY_LOW : SPI_POLARITY_HIGH;
}
if (phase != -1) {
init->CLKPhase = phase == 0 ? SPI_PHASE_1EDGE : SPI_PHASE_2EDGE;
}
if (bits != -1) {
init->DataSize = (bits == 16) ? SPI_DATASIZE_16BIT : SPI_DATASIZE_8BIT;
}
if (firstbit != -1) {
init->FirstBit = firstbit;
}
}
// TODO allow to take a list of pins to use
void spi_init(SPI_HandleTypeDef *spi, bool enable_nss_pin) {
// init the GPIO lines
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.Mode = GPIO_MODE_AF_PP;
GPIO_InitStructure.Speed = GPIO_SPEED_FAST;
GPIO_InitStructure.Pull = spi->Init.CLKPolarity == SPI_POLARITY_LOW ? GPIO_PULLDOWN : GPIO_PULLUP;
const pyb_spi_obj_t *self;
const pin_obj_t *pins[4];
pins[0] = NULL;
if (0) {
#if defined(MICROPY_HW_SPI1_SCK)
} else if (spi->Instance == SPI1) {
self = &pyb_spi_obj[0];
#if defined(MICROPY_HW_SPI1_NSS)
pins[0] = &MICROPY_HW_SPI1_NSS;
#endif
pins[1] = &MICROPY_HW_SPI1_SCK;
pins[2] = &MICROPY_HW_SPI1_MISO;
pins[3] = &MICROPY_HW_SPI1_MOSI;
// enable the SPI clock
__SPI1_CLK_ENABLE();
#endif
#if defined(MICROPY_HW_SPI2_SCK)
} else if (spi->Instance == SPI2) {
self = &pyb_spi_obj[1];
#if defined(MICROPY_HW_SPI2_NSS)
pins[0] = &MICROPY_HW_SPI2_NSS;
#endif
pins[1] = &MICROPY_HW_SPI2_SCK;
pins[2] = &MICROPY_HW_SPI2_MISO;
pins[3] = &MICROPY_HW_SPI2_MOSI;
// enable the SPI clock
__SPI2_CLK_ENABLE();
#endif
#if defined(MICROPY_HW_SPI3_SCK)
} else if (spi->Instance == SPI3) {
self = &pyb_spi_obj[2];
#if defined(MICROPY_HW_SPI3_NSS)
pins[0] = &MICROPY_HW_SPI3_NSS;
#endif
pins[1] = &MICROPY_HW_SPI3_SCK;
pins[2] = &MICROPY_HW_SPI3_MISO;
pins[3] = &MICROPY_HW_SPI3_MOSI;
// enable the SPI clock
__SPI3_CLK_ENABLE();
#endif
#if defined(MICROPY_HW_SPI4_SCK)
} else if (spi->Instance == SPI4) {
self = &pyb_spi_obj[3];
#if defined(MICROPY_HW_SPI4_NSS)
pins[0] = &MICROPY_HW_SPI4_NSS;
#endif
pins[1] = &MICROPY_HW_SPI4_SCK;
pins[2] = &MICROPY_HW_SPI4_MISO;
pins[3] = &MICROPY_HW_SPI4_MOSI;
// enable the SPI clock
__SPI4_CLK_ENABLE();
#endif
#if defined(MICROPY_HW_SPI5_SCK)
} else if (spi->Instance == SPI5) {
self = &pyb_spi_obj[4];
#if defined(MICROPY_HW_SPI5_NSS)
pins[0] = &MICROPY_HW_SPI5_NSS;
#endif
pins[1] = &MICROPY_HW_SPI5_SCK;
pins[2] = &MICROPY_HW_SPI5_MISO;
pins[3] = &MICROPY_HW_SPI5_MOSI;
// enable the SPI clock
__SPI5_CLK_ENABLE();
#endif
#if defined(MICROPY_HW_SPI6_SCK)
} else if (spi->Instance == SPI6) {
self = &pyb_spi_obj[5];
#if defined(MICROPY_HW_SPI6_NSS)
pins[0] = &MICROPY_HW_SPI6_NSS;
#endif
pins[1] = &MICROPY_HW_SPI6_SCK;
pins[2] = &MICROPY_HW_SPI6_MISO;
pins[3] = &MICROPY_HW_SPI6_MOSI;
// enable the SPI clock
__SPI6_CLK_ENABLE();
#endif
} else {
// SPI does not exist for this board (shouldn't get here, should be checked by caller)
return;
}
for (uint i = (enable_nss_pin && pins[0] ? 0 : 1); i < 4; i++) {
mp_hal_gpio_set_af(pins[i], &GPIO_InitStructure, AF_FN_SPI, (self - &pyb_spi_obj[0]) + 1);
}
// init the SPI device
if (HAL_SPI_Init(spi) != HAL_OK) {
// init error
// TODO should raise an exception, but this function is not necessarily going to be
// called via Python, so may not be properly wrapped in an NLR handler
printf("OSError: HAL_SPI_Init failed\n");
return;
}
// After calling HAL_SPI_Init() it seems that the DMA gets disconnected if
// it was previously configured. So we invalidate the DMA channel to force
// an initialisation the next time we use it.
dma_invalidate_channel(self->tx_dma_descr);
dma_invalidate_channel(self->rx_dma_descr);
}
void spi_deinit(SPI_HandleTypeDef *spi) {
HAL_SPI_DeInit(spi);
if (0) {
#if defined(MICROPY_HW_SPI1_SCK)
} else if (spi->Instance == SPI1) {
__SPI1_FORCE_RESET();
__SPI1_RELEASE_RESET();
__SPI1_CLK_DISABLE();
#endif
#if defined(MICROPY_HW_SPI2_SCK)
} else if (spi->Instance == SPI2) {
__SPI2_FORCE_RESET();
__SPI2_RELEASE_RESET();
__SPI2_CLK_DISABLE();
#endif
#if defined(MICROPY_HW_SPI3_SCK)
} else if (spi->Instance == SPI3) {
__SPI3_FORCE_RESET();
__SPI3_RELEASE_RESET();
__SPI3_CLK_DISABLE();
#endif
#if defined(MICROPY_HW_SPI4_SCK)
} else if (spi->Instance == SPI4) {
__SPI4_FORCE_RESET();
__SPI4_RELEASE_RESET();
__SPI4_CLK_DISABLE();
#endif
#if defined(MICROPY_HW_SPI5_SCK)
} else if (spi->Instance == SPI5) {
__SPI5_FORCE_RESET();
__SPI5_RELEASE_RESET();
__SPI5_CLK_DISABLE();
#endif
#if defined(MICROPY_HW_SPI6_SCK)
} else if (spi->Instance == SPI6) {
__SPI6_FORCE_RESET();
__SPI6_RELEASE_RESET();
__SPI6_CLK_DISABLE();
#endif
}
}
STATIC HAL_StatusTypeDef spi_wait_dma_finished(SPI_HandleTypeDef *spi, uint32_t timeout) {
// Note: we can't use WFI to idle in this loop because the DMA completion
// interrupt may occur before the WFI. Hence we miss it and have to wait
// until the next sys-tick (up to 1ms).
uint32_t start = HAL_GetTick();
while (HAL_SPI_GetState(spi) != HAL_SPI_STATE_READY) {
if (HAL_GetTick() - start >= timeout) {
return HAL_TIMEOUT;
}
}
return HAL_OK;
}
STATIC void spi_transfer(const pyb_spi_obj_t *self, size_t len, const uint8_t *src, uint8_t *dest, uint32_t timeout) {
// Note: there seems to be a problem sending 1 byte using DMA the first
// time directly after the SPI/DMA is initialised. The cause of this is
// unknown but we sidestep the issue by using polling for 1 byte transfer.
HAL_StatusTypeDef status;
if (dest == NULL) {
// send only
if (len == 1 || query_irq() == IRQ_STATE_DISABLED) {
status = HAL_SPI_Transmit(self->spi, (uint8_t*)src, len, timeout);
} else {
DMA_HandleTypeDef tx_dma;
dma_init(&tx_dma, self->tx_dma_descr, self->spi);
self->spi->hdmatx = &tx_dma;
self->spi->hdmarx = NULL;
status = HAL_SPI_Transmit_DMA(self->spi, (uint8_t*)src, len);
if (status == HAL_OK) {
status = spi_wait_dma_finished(self->spi, timeout);
}
dma_deinit(self->tx_dma_descr);
}
} else if (src == NULL) {
// receive only
if (len == 1 || query_irq() == IRQ_STATE_DISABLED) {
status = HAL_SPI_Receive(self->spi, dest, len, timeout);
} else {
DMA_HandleTypeDef tx_dma, rx_dma;
if (self->spi->Init.Mode == SPI_MODE_MASTER) {
// in master mode the HAL actually does a TransmitReceive call
dma_init(&tx_dma, self->tx_dma_descr, self->spi);
self->spi->hdmatx = &tx_dma;
} else {
self->spi->hdmatx = NULL;
}
dma_init(&rx_dma, self->rx_dma_descr, self->spi);
self->spi->hdmarx = &rx_dma;
status = HAL_SPI_Receive_DMA(self->spi, dest, len);
if (status == HAL_OK) {
status = spi_wait_dma_finished(self->spi, timeout);
}
if (self->spi->hdmatx != NULL) {
dma_deinit(self->tx_dma_descr);
}
dma_deinit(self->rx_dma_descr);
}
} else {
// send and receive
if (len == 1 || query_irq() == IRQ_STATE_DISABLED) {
status = HAL_SPI_TransmitReceive(self->spi, (uint8_t*)src, dest, len, timeout);
} else {
DMA_HandleTypeDef tx_dma, rx_dma;
dma_init(&tx_dma, self->tx_dma_descr, self->spi);
self->spi->hdmatx = &tx_dma;
dma_init(&rx_dma, self->rx_dma_descr, self->spi);
self->spi->hdmarx = &rx_dma;
status = HAL_SPI_TransmitReceive_DMA(self->spi, (uint8_t*)src, dest, len);
if (status == HAL_OK) {
status = spi_wait_dma_finished(self->spi, timeout);
}
dma_deinit(self->tx_dma_descr);
dma_deinit(self->rx_dma_descr);
}
}
if (status != HAL_OK) {
mp_hal_raise(status);
}
}
STATIC void spi_print(const mp_print_t *print, SPI_HandleTypeDef *spi, bool legacy) {
uint spi_num = 1; // default to SPI1
if (spi->Instance == SPI2) { spi_num = 2; }
else if (spi->Instance == SPI3) { spi_num = 3; }
#if defined(SPI4)
else if (spi->Instance == SPI4) { spi_num = 4; }
#endif
#if defined(SPI5)
else if (spi->Instance == SPI5) { spi_num = 5; }
#endif
#if defined(SPI6)
else if (spi->Instance == SPI6) { spi_num = 6; }
#endif
mp_printf(print, "SPI(%u", spi_num);
if (spi->State != HAL_SPI_STATE_RESET) {
if (spi->Init.Mode == SPI_MODE_MASTER) {
// compute baudrate
uint spi_clock;
if (spi->Instance == SPI2 || spi->Instance == SPI3) {
// SPI2 and SPI3 are on APB1
spi_clock = HAL_RCC_GetPCLK1Freq();
} else {
// SPI1, SPI4, SPI5 and SPI6 are on APB2
spi_clock = HAL_RCC_GetPCLK2Freq();
}
uint log_prescaler = (spi->Init.BaudRatePrescaler >> 3) + 1;
uint baudrate = spi_clock >> log_prescaler;
if (legacy) {
mp_printf(print, ", SPI.MASTER");
}
mp_printf(print, ", baudrate=%u", baudrate);
if (legacy) {
mp_printf(print, ", prescaler=%u", 1 << log_prescaler);
}
} else {
mp_printf(print, ", SPI.SLAVE");
}
mp_printf(print, ", polarity=%u, phase=%u, bits=%u", spi->Init.CLKPolarity == SPI_POLARITY_LOW ? 0 : 1, spi->Init.CLKPhase == SPI_PHASE_1EDGE ? 0 : 1, spi->Init.DataSize == SPI_DATASIZE_8BIT ? 8 : 16);
if (spi->Init.CRCCalculation == SPI_CRCCALCULATION_ENABLED) {
mp_printf(print, ", crc=0x%x", spi->Init.CRCPolynomial);
}
}
mp_print_str(print, ")");
}
/******************************************************************************/
/* MicroPython bindings for legacy pyb API */
SPI_HandleTypeDef *spi_get_handle(mp_obj_t o) {
if (!MP_OBJ_IS_TYPE(o, &pyb_spi_type)) {
mp_raise_ValueError("expecting an SPI object");
}
pyb_spi_obj_t *self = o;
return self->spi;
}
STATIC void pyb_spi_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
pyb_spi_obj_t *self = self_in;
spi_print(print, self->spi, true);
}
/// \method init(mode, baudrate=328125, *, polarity=1, phase=0, bits=8, firstbit=SPI.MSB, ti=False, crc=None)
///
/// Initialise the SPI bus with the given parameters:
///
/// - `mode` must be either `SPI.MASTER` or `SPI.SLAVE`.
/// - `baudrate` is the SCK clock rate (only sensible for a master).
STATIC mp_obj_t pyb_spi_init_helper(const pyb_spi_obj_t *self, mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_mode, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_baudrate, MP_ARG_INT, {.u_int = 328125} },
{ MP_QSTR_prescaler, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0xffffffff} },
{ MP_QSTR_polarity, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 1} },
{ MP_QSTR_phase, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_dir, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = SPI_DIRECTION_2LINES} },
{ MP_QSTR_bits, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 8} },
{ MP_QSTR_nss, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = SPI_NSS_SOFT} },
{ MP_QSTR_firstbit, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = SPI_FIRSTBIT_MSB} },
{ MP_QSTR_ti, MP_ARG_KW_ONLY | MP_ARG_BOOL, {.u_bool = false} },
{ MP_QSTR_crc, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
};
// parse args
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
// set the SPI configuration values
SPI_InitTypeDef *init = &self->spi->Init;
init->Mode = args[0].u_int;
spi_set_params(self->spi, args[2].u_int, args[1].u_int, args[3].u_int, args[4].u_int,
args[6].u_int, args[8].u_int);
init->Direction = args[5].u_int;
init->NSS = args[7].u_int;
init->TIMode = args[9].u_bool ? SPI_TIMODE_ENABLED : SPI_TIMODE_DISABLED;
if (args[10].u_obj == mp_const_none) {
init->CRCCalculation = SPI_CRCCALCULATION_DISABLED;
init->CRCPolynomial = 0;
} else {
init->CRCCalculation = SPI_CRCCALCULATION_ENABLED;
init->CRCPolynomial = mp_obj_get_int(args[10].u_obj);
}
// init the SPI bus
spi_init(self->spi, init->NSS != SPI_NSS_SOFT);
return mp_const_none;
}
/// \classmethod \constructor(bus, ...)
///
/// Construct an SPI object on the given bus. `bus` can be 1 or 2.
/// With no additional parameters, the SPI object is created but not
/// initialised (it has the settings from the last initialisation of
/// the bus, if any). If extra arguments are given, the bus is initialised.
/// See `init` for parameters of initialisation.
///
/// The physical pins of the SPI busses are:
///
/// - `SPI(1)` is on the X position: `(NSS, SCK, MISO, MOSI) = (X5, X6, X7, X8) = (PA4, PA5, PA6, PA7)`
/// - `SPI(2)` is on the Y position: `(NSS, SCK, MISO, MOSI) = (Y5, Y6, Y7, Y8) = (PB12, PB13, PB14, PB15)`
///
/// At the moment, the NSS pin is not used by the SPI driver and is free
/// for other use.
STATIC mp_obj_t pyb_spi_make_new(const mp_obj_type_t *type, mp_uint_t n_args, mp_uint_t n_kw, const mp_obj_t *args) {
// check arguments
mp_arg_check_num(n_args, n_kw, 1, MP_OBJ_FUN_ARGS_MAX, true);
// work out SPI bus
int spi_id = spi_find(args[0]);
// get SPI object
const pyb_spi_obj_t *spi_obj = &pyb_spi_obj[spi_id - 1];
if (n_args > 1 || n_kw > 0) {
// start the peripheral
mp_map_t kw_args;
mp_map_init_fixed_table(&kw_args, n_kw, args + n_args);
pyb_spi_init_helper(spi_obj, n_args - 1, args + 1, &kw_args);
}
return (mp_obj_t)spi_obj;
}
STATIC mp_obj_t pyb_spi_init(mp_uint_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
return pyb_spi_init_helper(args[0], n_args - 1, args + 1, kw_args);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_spi_init_obj, 1, pyb_spi_init);
/// \method deinit()
/// Turn off the SPI bus.
STATIC mp_obj_t pyb_spi_deinit(mp_obj_t self_in) {
pyb_spi_obj_t *self = self_in;
spi_deinit(self->spi);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_spi_deinit_obj, pyb_spi_deinit);
/// \method send(send, *, timeout=5000)
/// Send data on the bus:
///
/// - `send` is the data to send (an integer to send, or a buffer object).
/// - `timeout` is the timeout in milliseconds to wait for the send.
///
/// Return value: `None`.
STATIC mp_obj_t pyb_spi_send(mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
// TODO assumes transmission size is 8-bits wide
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_send, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
};
// parse args
pyb_spi_obj_t *self = pos_args[0];
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
// get the buffer to send from
mp_buffer_info_t bufinfo;
uint8_t data[1];
pyb_buf_get_for_send(args[0].u_obj, &bufinfo, data);
// send the data
spi_transfer(self, bufinfo.len, bufinfo.buf, NULL, args[1].u_int);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_spi_send_obj, 1, pyb_spi_send);
/// \method recv(recv, *, timeout=5000)
///
/// Receive data on the bus:
///
/// - `recv` can be an integer, which is the number of bytes to receive,
/// or a mutable buffer, which will be filled with received bytes.
/// - `timeout` is the timeout in milliseconds to wait for the receive.
///
/// Return value: if `recv` is an integer then a new buffer of the bytes received,
/// otherwise the same buffer that was passed in to `recv`.
STATIC mp_obj_t pyb_spi_recv(mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
// TODO assumes transmission size is 8-bits wide
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_recv, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
};
// parse args
pyb_spi_obj_t *self = pos_args[0];
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
// get the buffer to receive into
vstr_t vstr;
mp_obj_t o_ret = pyb_buf_get_for_recv(args[0].u_obj, &vstr);
// receive the data
spi_transfer(self, vstr.len, NULL, (uint8_t*)vstr.buf, args[1].u_int);
// return the received data
if (o_ret != MP_OBJ_NULL) {
return o_ret;
} else {
return mp_obj_new_str_from_vstr(&mp_type_bytes, &vstr);
}
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_spi_recv_obj, 1, pyb_spi_recv);
/// \method send_recv(send, recv=None, *, timeout=5000)
///
/// Send and receive data on the bus at the same time:
///
/// - `send` is the data to send (an integer to send, or a buffer object).
/// - `recv` is a mutable buffer which will be filled with received bytes.
/// It can be the same as `send`, or omitted. If omitted, a new buffer will
/// be created.
/// - `timeout` is the timeout in milliseconds to wait for the receive.
///
/// Return value: the buffer with the received bytes.
STATIC mp_obj_t pyb_spi_send_recv(mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
// TODO assumes transmission size is 8-bits wide
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_send, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_recv, MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
};
// parse args
pyb_spi_obj_t *self = pos_args[0];
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
// get buffers to send from/receive to
mp_buffer_info_t bufinfo_send;
uint8_t data_send[1];
mp_buffer_info_t bufinfo_recv;
vstr_t vstr_recv;
mp_obj_t o_ret;
if (args[0].u_obj == args[1].u_obj) {
// same object for send and receive, it must be a r/w buffer
mp_get_buffer_raise(args[0].u_obj, &bufinfo_send, MP_BUFFER_RW);
bufinfo_recv = bufinfo_send;
o_ret = args[0].u_obj;
} else {
// get the buffer to send from
pyb_buf_get_for_send(args[0].u_obj, &bufinfo_send, data_send);
// get the buffer to receive into
if (args[1].u_obj == MP_OBJ_NULL) {
// only send argument given, so create a fresh buffer of the send length
vstr_init_len(&vstr_recv, bufinfo_send.len);
bufinfo_recv.len = vstr_recv.len;
bufinfo_recv.buf = vstr_recv.buf;
o_ret = MP_OBJ_NULL;
} else {
// recv argument given
mp_get_buffer_raise(args[1].u_obj, &bufinfo_recv, MP_BUFFER_WRITE);
if (bufinfo_recv.len != bufinfo_send.len) {
nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, "recv must be same length as send"));
}
o_ret = args[1].u_obj;
}
}
// do the transfer
spi_transfer(self, bufinfo_send.len, bufinfo_send.buf, bufinfo_recv.buf, args[2].u_int);
// return the received data
if (o_ret != MP_OBJ_NULL) {
return o_ret;
} else {
return mp_obj_new_str_from_vstr(&mp_type_bytes, &vstr_recv);
}
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_spi_send_recv_obj, 1, pyb_spi_send_recv);
STATIC const mp_map_elem_t pyb_spi_locals_dict_table[] = {
// instance methods
{ MP_OBJ_NEW_QSTR(MP_QSTR_init), (mp_obj_t)&pyb_spi_init_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_deinit), (mp_obj_t)&pyb_spi_deinit_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_read), (mp_obj_t)&mp_machine_spi_read_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_readinto), (mp_obj_t)&mp_machine_spi_readinto_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_write), (mp_obj_t)&mp_machine_spi_write_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_write_readinto), (mp_obj_t)&mp_machine_spi_write_readinto_obj },
// legacy methods
{ MP_OBJ_NEW_QSTR(MP_QSTR_send), (mp_obj_t)&pyb_spi_send_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_recv), (mp_obj_t)&pyb_spi_recv_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_send_recv), (mp_obj_t)&pyb_spi_send_recv_obj },
// class constants
/// \constant MASTER - for initialising the bus to master mode
/// \constant SLAVE - for initialising the bus to slave mode
/// \constant MSB - set the first bit to MSB
/// \constant LSB - set the first bit to LSB
{ MP_OBJ_NEW_QSTR(MP_QSTR_MASTER), MP_OBJ_NEW_SMALL_INT(SPI_MODE_MASTER) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_SLAVE), MP_OBJ_NEW_SMALL_INT(SPI_MODE_SLAVE) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_MSB), MP_OBJ_NEW_SMALL_INT(SPI_FIRSTBIT_MSB) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_LSB), MP_OBJ_NEW_SMALL_INT(SPI_FIRSTBIT_LSB) },
/* TODO
{ MP_OBJ_NEW_QSTR(MP_QSTR_DIRECTION_2LINES ((uint32_t)0x00000000)
{ MP_OBJ_NEW_QSTR(MP_QSTR_DIRECTION_2LINES_RXONLY SPI_CR1_RXONLY
{ MP_OBJ_NEW_QSTR(MP_QSTR_DIRECTION_1LINE SPI_CR1_BIDIMODE
{ MP_OBJ_NEW_QSTR(MP_QSTR_NSS_SOFT SPI_CR1_SSM
{ MP_OBJ_NEW_QSTR(MP_QSTR_NSS_HARD_INPUT ((uint32_t)0x00000000)
{ MP_OBJ_NEW_QSTR(MP_QSTR_NSS_HARD_OUTPUT ((uint32_t)0x00040000)
*/
};
STATIC MP_DEFINE_CONST_DICT(pyb_spi_locals_dict, pyb_spi_locals_dict_table);
STATIC void spi_transfer_machine(mp_obj_base_t *self_in, size_t len, const uint8_t *src, uint8_t *dest) {
spi_transfer((pyb_spi_obj_t*)self_in, len, src, dest, 100);
}
STATIC const mp_machine_spi_p_t pyb_spi_p = {
.transfer = spi_transfer_machine,
};
const mp_obj_type_t pyb_spi_type = {
{ &mp_type_type },
.name = MP_QSTR_SPI,
.print = pyb_spi_print,
.make_new = pyb_spi_make_new,
.protocol = &pyb_spi_p,
.locals_dict = (mp_obj_t)&pyb_spi_locals_dict,
};
/******************************************************************************/
/* MicroPython bindings for machine API */
// for make_new
enum {
ARG_NEW_id,
ARG_NEW_baudrate,
ARG_NEW_polarity,
ARG_NEW_phase,
ARG_NEW_bits,
ARG_NEW_firstbit,
ARG_NEW_sck,
ARG_NEW_mosi,
ARG_NEW_miso
};
// for init
enum {
ARG_INIT_baudrate,
ARG_INIT_polarity,
ARG_INIT_phase,
ARG_INIT_bits,
ARG_INIT_firstbit
};
STATIC mp_obj_t machine_soft_spi_make_new(mp_arg_val_t *args);
STATIC void machine_soft_spi_init(mp_obj_t self, mp_arg_val_t *args);
STATIC void machine_soft_spi_deinit(mp_obj_t self);
STATIC mp_obj_t machine_hard_spi_make_new(mp_arg_val_t *args);
STATIC void machine_hard_spi_init(mp_obj_t self, mp_arg_val_t *args);
STATIC void machine_hard_spi_deinit(mp_obj_t self);
/* common code for both soft and hard implementations *************************/
STATIC mp_obj_t machine_spi_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_id, MP_ARG_OBJ, {.u_obj = MP_OBJ_NEW_SMALL_INT(-1)} },
{ MP_QSTR_baudrate, MP_ARG_INT, {.u_int = 500000} },
{ MP_QSTR_polarity, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_phase, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_bits, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 8} },
{ MP_QSTR_firstbit, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = SPI_FIRSTBIT_MSB} },
{ MP_QSTR_sck, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_mosi, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_miso, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
};
// parse args
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);
if (args[ARG_NEW_id].u_obj == MP_OBJ_NEW_SMALL_INT(-1)) {
// software SPI
return machine_soft_spi_make_new(args);
} else {
// hardware peripheral id given
return machine_hard_spi_make_new(args);
}
}
STATIC mp_obj_t machine_spi_init(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_baudrate, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
{ MP_QSTR_polarity, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
{ MP_QSTR_phase, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
{ MP_QSTR_bits, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
{ MP_QSTR_firstbit, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
};
// parse args
mp_obj_t self = pos_args[0];
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
// dispatch to specific implementation
if (mp_obj_get_type(self) == &machine_soft_spi_type) {
machine_soft_spi_init(self, args);
} else {
machine_hard_spi_init(self, args);
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(machine_spi_init_obj, 1, machine_spi_init);
STATIC mp_obj_t machine_spi_deinit(mp_obj_t self) {
// dispatch to specific implementation
if (mp_obj_get_type(self) == &machine_soft_spi_type) {
machine_soft_spi_deinit(self);
} else {
machine_hard_spi_deinit(self);
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_spi_deinit_obj, machine_spi_deinit);
STATIC const mp_rom_map_elem_t machine_spi_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&machine_spi_init_obj) },
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&machine_spi_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_machine_spi_read_obj) },
{ MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_machine_spi_readinto_obj) },
{ MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_machine_spi_write_obj) },
{ MP_ROM_QSTR(MP_QSTR_write_readinto), MP_ROM_PTR(&mp_machine_spi_write_readinto_obj) },
{ MP_ROM_QSTR(MP_QSTR_MSB), MP_ROM_INT(SPI_FIRSTBIT_MSB) },
{ MP_ROM_QSTR(MP_QSTR_LSB), MP_ROM_INT(SPI_FIRSTBIT_LSB) },
};
STATIC MP_DEFINE_CONST_DICT(machine_spi_locals_dict, machine_spi_locals_dict_table);
/* code for soft implementation ***********************************************/
STATIC uint32_t baudrate_from_delay_half(uint32_t delay_half) {
return 500000 / delay_half;
}
STATIC uint32_t baudrate_to_delay_half(uint32_t baudrate) {
uint32_t delay_half = 500000 / baudrate;
// round delay_half up so that: actual_baudrate <= requested_baudrate
if (500000 % baudrate != 0) {
delay_half += 1;
}
return delay_half;
}
STATIC void machine_soft_spi_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
mp_machine_soft_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
mp_printf(print, "SPI(-1, baudrate=%u, polarity=%u, phase=%u, sck=%q, mosi=%q, miso=%q)",
baudrate_from_delay_half(self->delay_half), self->polarity, self->phase,
self->sck->name, self->mosi->name, self->miso->name);
}
STATIC mp_obj_t machine_soft_spi_make_new(mp_arg_val_t *args) {
// create new object
mp_machine_soft_spi_obj_t *self = m_new_obj(mp_machine_soft_spi_obj_t);
self->base.type = &machine_soft_spi_type;
// set parameters
self->delay_half = baudrate_to_delay_half(args[ARG_NEW_baudrate].u_int);
self->polarity = args[ARG_NEW_polarity].u_int;
self->phase = args[ARG_NEW_phase].u_int;
if (args[ARG_NEW_bits].u_int != 8) {
mp_raise_ValueError("bits must be 8");
}
if (args[ARG_NEW_firstbit].u_int != SPI_FIRSTBIT_MSB) {
mp_raise_ValueError("firstbit must be MSB");
}
if (args[ARG_NEW_sck].u_obj == MP_OBJ_NULL
|| args[ARG_NEW_mosi].u_obj == MP_OBJ_NULL
|| args[ARG_NEW_miso].u_obj == MP_OBJ_NULL) {
mp_raise_ValueError("must specify all of sck/mosi/miso");
}
self->sck = mp_hal_get_pin_obj(args[ARG_NEW_sck].u_obj);
self->mosi = mp_hal_get_pin_obj(args[ARG_NEW_mosi].u_obj);
self->miso = mp_hal_get_pin_obj(args[ARG_NEW_miso].u_obj);
// configure pins
mp_hal_pin_write(self->sck, self->polarity);
mp_hal_pin_output(self->sck);
mp_hal_pin_output(self->mosi);
mp_hal_pin_input(self->miso);
return MP_OBJ_FROM_PTR(self);
}
STATIC void machine_soft_spi_init(mp_obj_t self_in, mp_arg_val_t *args) {
mp_machine_soft_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
// update parameters
if (args[ARG_INIT_baudrate].u_int != -1) {
self->delay_half = baudrate_to_delay_half(args[ARG_INIT_baudrate].u_int);
}
if (args[ARG_INIT_polarity].u_int != -1) {
self->polarity = args[ARG_INIT_polarity].u_int;
}
if (args[ARG_INIT_phase].u_int != -1) {
self->phase = args[ARG_INIT_phase].u_int;
}
}
STATIC void machine_soft_spi_deinit(mp_obj_t self) {
// nothing to do
(void)self;
}
STATIC const mp_machine_spi_p_t machine_soft_spi_p = {
.transfer = mp_machine_soft_spi_transfer,
};
const mp_obj_type_t machine_soft_spi_type = {
{ &mp_type_type },
.name = MP_QSTR_SoftSPI,
.print = machine_soft_spi_print,
.make_new = machine_spi_make_new,
.protocol = &machine_soft_spi_p,
.locals_dict = (mp_obj_t)&machine_spi_locals_dict,
};
/* code for hard implementation ***********************************************/
typedef struct _machine_hard_spi_obj_t {
mp_obj_base_t base;
const pyb_spi_obj_t *pyb;
} machine_hard_spi_obj_t;
STATIC const machine_hard_spi_obj_t machine_hard_spi_obj[] = {
{{&machine_hard_spi_type}, &pyb_spi_obj[0]},
{{&machine_hard_spi_type}, &pyb_spi_obj[1]},
{{&machine_hard_spi_type}, &pyb_spi_obj[2]},
{{&machine_hard_spi_type}, &pyb_spi_obj[3]},
{{&machine_hard_spi_type}, &pyb_spi_obj[4]},
{{&machine_hard_spi_type}, &pyb_spi_obj[5]},
};
STATIC void machine_hard_spi_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
machine_hard_spi_obj_t *self = self_in;
spi_print(print, self->pyb->spi, false);
}
STATIC mp_obj_t machine_hard_spi_make_new(mp_arg_val_t *args) {
// get static peripheral object
int spi_id = spi_find(args[ARG_NEW_id].u_obj);
const machine_hard_spi_obj_t *self = &machine_hard_spi_obj[spi_id - 1];
// here we would check the sck/mosi/miso pins and configure them, but it's not implemented
if (args[ARG_NEW_sck].u_obj != MP_OBJ_NULL
|| args[ARG_NEW_mosi].u_obj != MP_OBJ_NULL
|| args[ARG_NEW_miso].u_obj != MP_OBJ_NULL) {
mp_raise_ValueError("explicit choice of sck/mosi/miso is not implemented");
}
// set the SPI configuration values
SPI_InitTypeDef *init = &self->pyb->spi->Init;
init->Mode = SPI_MODE_MASTER;
// these parameters are not currently configurable
init->Direction = SPI_DIRECTION_2LINES;
init->NSS = SPI_NSS_SOFT;
init->TIMode = SPI_TIMODE_DISABLED;
init->CRCCalculation = SPI_CRCCALCULATION_DISABLED;
init->CRCPolynomial = 0;
// set configurable paramaters
spi_set_params(self->pyb->spi, 0xffffffff, args[ARG_NEW_baudrate].u_int,
args[ARG_NEW_polarity].u_int, args[ARG_NEW_phase].u_int, args[ARG_NEW_bits].u_int,
args[ARG_NEW_firstbit].u_int);
// init the SPI bus
spi_init(self->pyb->spi, false);
return MP_OBJ_FROM_PTR(self);
}
STATIC void machine_hard_spi_init(mp_obj_t self_in, mp_arg_val_t *args) {
machine_hard_spi_obj_t *self = self_in;
// set the SPI configuration values
spi_set_params(self->pyb->spi, 0xffffffff, args[ARG_INIT_baudrate].u_int,
args[ARG_INIT_polarity].u_int, args[ARG_INIT_phase].u_int, args[ARG_INIT_bits].u_int,
args[ARG_INIT_firstbit].u_int);
// re-init the SPI bus
spi_init(self->pyb->spi, false);
}
STATIC void machine_hard_spi_deinit(mp_obj_t self_in) {
machine_hard_spi_obj_t *self = self_in;
spi_deinit(self->pyb->spi);
}
STATIC void machine_hard_spi_transfer(mp_obj_base_t *self_in, size_t len, const uint8_t *src, uint8_t *dest) {
machine_hard_spi_obj_t *self = (machine_hard_spi_obj_t*)self_in;
spi_transfer(self->pyb, len, src, dest, 100);
}
STATIC const mp_machine_spi_p_t machine_hard_spi_p = {
.transfer = machine_hard_spi_transfer,
};
const mp_obj_type_t machine_hard_spi_type = {
{ &mp_type_type },
.name = MP_QSTR_SPI,
.print = machine_hard_spi_print,
.make_new = machine_spi_make_new,
.protocol = &machine_hard_spi_p,
.locals_dict = (mp_obj_t)&machine_spi_locals_dict,
};
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