PN532 SPI模式STM32开发
时间: 2023-07-02 22:20:58 浏览: 183
好的,关于PN532在STM32上的SPI模式开发,我可以给您一些简单的参考。
首先,您需要确保您的STM32与PN532之间通过SPI接口进行连接。接下来,您需要使用STM32的SPI库来初始化SPI接口,并设置SPI的参数(如时钟分频、数据位数等)。然后,您需要按照PN532的通信协议来发送数据和接收数据。
以下是一个简单的示例代码,可以帮助您开始:
```c
#include "stm32f4xx.h"
#include "spi.h"
#define PN532_SPI_CS_PORT GPIOB
#define PN532_SPI_CS_PIN GPIO_Pin_12
void PN532_SPI_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
SPI_InitTypeDef SPI_InitStructure;
/* Enable SPI clock and GPIO clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA | RCC_AHB1Periph_GPIOB, ENABLE);
/* Configure SPI pins */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Configure CS pin */
GPIO_InitStructure.GPIO_Pin = PN532_SPI_CS_PIN;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_Init(PN532_SPI_CS_PORT, &GPIO_InitStructure);
/* Connect SPI pins to SPI alternate function */
GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource7, GPIO_AF_SPI1);
/* Configure SPI */
SPI_I2S_DeInit(SPI1);
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_16;
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_InitStructure.SPI_CRCPolynomial = 7;
SPI_Init(SPI1, &SPI_InitStructure);
/* Enable SPI */
SPI_Cmd(SPI1, ENABLE);
/* Set CS pin high */
GPIO_SetBits(PN532_SPI_CS_PORT, PN532_SPI_CS_PIN);
}
void PN532_SPI_Write(uint8_t* data, uint16_t len)
{
/* Set CS pin low */
GPIO_ResetBits(PN532_SPI_CS_PORT, PN532_SPI_CS_PIN);
/* Send data */
for (uint16_t i = 0; i < len; i++) {
SPI_I2S_SendData(SPI1, data[i]);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_BSY) == SET);
}
/* Set CS pin high */
GPIO_SetBits(PN532_SPI_CS_PORT, PN532_SPI_CS_PIN);
}
void PN532_SPI_Read(uint8_t* data, uint16_t len)
{
/* Set CS pin low */
GPIO_ResetBits(PN532_SPI_CS_PORT, PN532_SPI_CS_PIN);
/* Receive data */
for (uint16_t i = 0; i < len; i++) {
SPI_I2S_SendData(SPI1, 0xFF);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_BSY) == SET);
data[i] = SPI_I2S_ReceiveData(SPI1);
}
/* Set CS pin high */
GPIO_SetBits(PN532_SPI_CS_PORT, PN532_SPI_CS_PIN);
}
```
在此示例中,我们使用SPI1作为SPI接口,并将SCK、MISO、MOSI分别连接到PA5、PA6、PA7。CS引脚连接到PB12。您需要根据您的硬件连接来更改这些引脚。
在PN532_SPI_Init函数中,我们初始化SPI接口,并将CS引脚初始化为输出模式。在PN532_SPI_Write和PN532_SPI_Read函数中,我们分别用于发送和接收数据。在发送和接收数据时,我们需要检查SPI状态寄存器中的标志位,以确保数据成功发送和接收。
请注意,此示例代码仅用于参考。您需要根据您的具体要求进行修改和调整。
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