mbed library sources
Dependents: frdm_kl05z_gpio_test
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Diff: targets/hal/TARGET_STM/TARGET_NUCLEO_F103RB/spi_api.c
- Revision:
- 52:a51c77007319
- Child:
- 56:99eb381a3269
diff -r 7838415c99e7 -r a51c77007319 targets/hal/TARGET_STM/TARGET_NUCLEO_F103RB/spi_api.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/hal/TARGET_STM/TARGET_NUCLEO_F103RB/spi_api.c Mon Dec 02 11:30:05 2013 +0000 @@ -0,0 +1,281 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2013 ARM Limited + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +//============================================================================== +// STM32F103 +//============================================================================== +#include "spi_api.h" + +#if DEVICE_SPI + +#include <math.h> +#include "cmsis.h" +#include "pinmap.h" +#include "error.h" + +static const PinMap PinMap_SPI_MOSI[] = { + {PA_7, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 0)}, + {PB_5, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 1)}, // Remap + {NC, NC, 0} +}; + +static const PinMap PinMap_SPI_MISO[] = { + {PA_6, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 0)}, + {PB_4, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 1)}, // Remap + {NC, NC, 0} +}; + +static const PinMap PinMap_SPI_SCLK[] = { + {PA_5, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 0)}, + {PB_3, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 1)}, // Remap + {NC, NC, 0} +}; + +// Only used in Slave mode +static const PinMap PinMap_SPI_SSEL[] = { + {PA_4, SPI_1, STM_PIN_DATA(GPIO_Mode_IN_FLOATING, 0)}, + {PA_15, SPI_1, STM_PIN_DATA(GPIO_Mode_IN_FLOATING, 1)}, // Remap + {NC, NC, 0} +}; + +void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) { + + SPI_TypeDef *spi; + SPI_InitTypeDef SPI_InitStructure; + + // Determine the SPI to use + SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI); + SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO); + SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK); + SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL); + + SPIName spi_data = (SPIName)pinmap_merge(spi_mosi, spi_miso); + SPIName spi_cntl = (SPIName)pinmap_merge(spi_sclk, spi_ssel); + + obj->spi = (SPIName)pinmap_merge(spi_data, spi_cntl); + + if (obj->spi == (SPIName)NC) { + error("SPI pinout mapping failed"); + } + + // Get SPI registers structure address + spi = (SPI_TypeDef *)(obj->spi); + + // Enable SPI clock + if (obj->spi == SPI_1) { + RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE); + } + if (obj->spi == SPI_2) { + RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2, ENABLE); + } + + // Configure the SPI pins + pinmap_pinout(mosi, PinMap_SPI_MOSI); + pinmap_pinout(miso, PinMap_SPI_MISO); + pinmap_pinout(sclk, PinMap_SPI_SCLK); + + // Save new values + obj->bits = SPI_DataSize_8b; + obj->cpol = SPI_CPOL_Low; + obj->cpha = SPI_CPHA_1Edge; + obj->br_presc = SPI_BaudRatePrescaler_64; // Closest to 1MHz (72MHz/64 = 1.125MHz) + + if (ssel == NC) { // Master + obj->mode = SPI_Mode_Master; + obj->nss = SPI_NSS_Soft; + } + else { // Slave + pinmap_pinout(ssel, PinMap_SPI_SSEL); + obj->mode = SPI_Mode_Slave; + obj->nss = SPI_NSS_Hard; + } + + // SPI configuration + SPI_InitStructure.SPI_Mode = obj->mode; + SPI_InitStructure.SPI_NSS = obj->nss; + SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex; + SPI_InitStructure.SPI_DataSize = obj->bits; + SPI_InitStructure.SPI_CPOL = obj->cpol; + SPI_InitStructure.SPI_CPHA = obj->cpha; + SPI_InitStructure.SPI_BaudRatePrescaler = obj->br_presc; + SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; + SPI_InitStructure.SPI_CRCPolynomial = 7; + SPI_Init(spi, &SPI_InitStructure); + + SPI_Cmd(spi, ENABLE); +} + +void spi_free(spi_t *obj) { + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + SPI_I2S_DeInit(spi); +} + +void spi_format(spi_t *obj, int bits, int mode, int slave) { + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + SPI_InitTypeDef SPI_InitStructure; + + // Save new values + + if (bits == 8) { + obj->bits = SPI_DataSize_8b; + } + else { + obj->bits = SPI_DataSize_16b; + } + + switch (mode) { + case 0: + obj->cpol = SPI_CPOL_Low; + obj->cpha = SPI_CPHA_1Edge; + break; + case 1: + obj->cpol = SPI_CPOL_Low; + obj->cpha = SPI_CPHA_2Edge; + break; + case 2: + obj->cpol = SPI_CPOL_High; + obj->cpha = SPI_CPHA_1Edge; + break; + default: + obj->cpol = SPI_CPOL_High; + obj->cpha = SPI_CPHA_2Edge; + break; + } + + if (slave == 0) { + obj->mode = SPI_Mode_Master; + obj->nss = SPI_NSS_Soft; + } + else { + obj->mode = SPI_Mode_Slave; + obj->nss = SPI_NSS_Hard; + } + + SPI_Cmd(spi, DISABLE); + + SPI_InitStructure.SPI_Mode = obj->mode; + SPI_InitStructure.SPI_NSS = obj->nss; + SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex; + SPI_InitStructure.SPI_DataSize = obj->bits; + SPI_InitStructure.SPI_CPOL = obj->cpol; + SPI_InitStructure.SPI_CPHA = obj->cpha; + SPI_InitStructure.SPI_BaudRatePrescaler = obj->br_presc; + SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; + SPI_InitStructure.SPI_CRCPolynomial = 7; + SPI_Init(spi, &SPI_InitStructure); + + SPI_Cmd(spi, ENABLE); +} + +void spi_frequency(spi_t *obj, int hz) { + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + SPI_InitTypeDef SPI_InitStructure; + + // Get SPI clock frequency + uint32_t PCLK = SystemCoreClock >> 1; + + // Choose the baud rate divisor (between 2 and 256) + uint32_t divisor = PCLK / hz; + + // Find the nearest power-of-2 + divisor = (divisor > 0 ? divisor-1 : 0); + divisor |= divisor >> 1; + divisor |= divisor >> 2; + divisor |= divisor >> 4; + divisor |= divisor >> 8; + divisor |= divisor >> 16; + divisor++; + + uint32_t baud_rate = __builtin_ffs(divisor) - 2; + + // Save new value + obj->br_presc = ((baud_rate > 7) ? (7 << 3) : (baud_rate << 3)); + + SPI_Cmd(spi, DISABLE); + + SPI_InitStructure.SPI_Mode = obj->mode; + SPI_InitStructure.SPI_NSS = obj->nss; + SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex; + SPI_InitStructure.SPI_DataSize = obj->bits; + SPI_InitStructure.SPI_CPOL = obj->cpol; + SPI_InitStructure.SPI_CPHA = obj->cpha; + SPI_InitStructure.SPI_BaudRatePrescaler = obj->br_presc; + SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; + SPI_InitStructure.SPI_CRCPolynomial = 7; + SPI_Init(spi, &SPI_InitStructure); + + SPI_Cmd(spi, ENABLE); +} + +static inline int ssp_readable(spi_t *obj) { + int status; + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + // Check if data is received + status = ((SPI_I2S_GetFlagStatus(spi, SPI_I2S_FLAG_RXNE) != RESET) ? 1 : 0); + return status; +} + +static inline int ssp_writeable(spi_t *obj) { + int status; + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + // Check if data is transmitted + status = ((SPI_I2S_GetFlagStatus(spi, SPI_I2S_FLAG_TXE) != RESET) ? 1 : 0); + return status; +} + +static inline void ssp_write(spi_t *obj, int value) { + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + while (!ssp_writeable(obj)); + SPI_I2S_SendData(spi, (uint16_t)value); +} + +static inline int ssp_read(spi_t *obj) { + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + while (!ssp_readable(obj)); + return (int)SPI_I2S_ReceiveData(spi); +} + +static inline int ssp_busy(spi_t *obj) { + int status; + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + status = ((SPI_I2S_GetFlagStatus(spi, SPI_I2S_FLAG_BSY) != RESET) ? 1 : 0); + return status; +} + +int spi_master_write(spi_t *obj, int value) { + ssp_write(obj, value); + return ssp_read(obj); +} + +int spi_slave_receive(spi_t *obj) { + return (ssp_readable(obj) && !ssp_busy(obj)) ? (1) : (0); +}; + +int spi_slave_read(spi_t *obj) { + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + return (int)SPI_I2S_ReceiveData(spi); +} + +void spi_slave_write(spi_t *obj, int value) { + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + while (!ssp_writeable(obj)); + SPI_I2S_SendData(spi, (uint16_t)value); +} + +int spi_busy(spi_t *obj) { + return ssp_busy(obj); +} + +#endif