RT-Thread-【FRDM-MCXA156测评】- P3T1755模块RT-Thread问答社区

【FRDM-MCXA156测评】- P3T1755模块

发布于 2025-02-26 10:24:35 浏览：172 订阅该版

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# 【FRDM-MCXA156测评】- P3T1755模块

# 模块介绍

FRDM-MCXA156板载了P3T1755模块，P3T1755DP是精确的温度数字转换器，精度为±0.5°C，温度范围为–40°C到+125°C。它搭载了片上带隙温度传感器，采用模数转换技术，具有超温检测功能。温度寄存器始终存储12位二进制补码数据，温度分辨率为0.0625°C。P3T1755DP可配置为不同的工作模式：连续转换模式、单一转换模式或关闭模式。

该设备支持2线串行I3C（高达12.5MHz）和I²C（高达3.4MHz）作为通信接口。在I²C中，该设备最多支持4个目标地址和警报功能。在I3C中，该设备支持带内中断功能（IBI），使用同一总线报告警报中断。

由于RT-Thread目前还不支持I3C框架，所以只能暂时用I2C来读取。

# 硬件连接

![](https://cdn.jsdelivr.net/gh/CYFS3/Typroa/202503112112706.png)

由原理图可知，P3T1755所用到的引脚为P0_16(SDA)、P0_17(SCL)。由于当前RT-Thread 主仓中的FRDM-MCXA156都是最小的配置，所以我们要使能I2C和初始化IO口。

# 配置过程

## 使能板载模块

![PixPin_2025-02-26_09-50-29](https://cdn.jsdelivr.net/gh/CYFS3/Typroa/202502261024785.png)

## 配置i2c引脚

添加在bsp\nxp\mcx\mcxa\frdm-mcxa156\board\MCUX_Config\board\pin_mux.c中的void BOARD_InitPins(void)函数中。

~~~c
 /* LPI2C0 peripheral is released from reset */
    RESET_ReleasePeripheralReset(kLPI2C0_RST_SHIFT_RSTn);
    const port_pin_config_t port0_16_pin83_config = {/* Internal pull-up resistor is enabled */
                                                     .pullSelect = kPORT_PullUp,
                                                     /* Low internal pull resistor value is selected. */
                                                     .pullValueSelect = kPORT_LowPullResistor,
                                                     /* Fast slew rate is configured */
                                                     .slewRate = kPORT_FastSlewRate,
                                                     /* Passive input filter is disabled */
                                                     .passiveFilterEnable = kPORT_PassiveFilterDisable,
                                                     /* Open drain output is disabled */
                                                     .openDrainEnable = kPORT_OpenDrainDisable,
                                                     /* Low drive strength is configured */
                                                     .driveStrength = kPORT_LowDriveStrength,
                                                     /* Normal drive strength is configured */
                                                     .driveStrength1 = kPORT_NormalDriveStrength,
                                                     /* Pin is configured as LPI2C0_SDA */
                                                     .mux = kPORT_MuxAlt2,
                                                     /* Digital input enabled */
                                                     .inputBuffer = kPORT_InputBufferEnable,
                                                     /* Digital input is not inverted */
                                                     .invertInput = kPORT_InputNormal,
                                                     /* Pin Control Register fields [15:0] are not locked */
                                                     .lockRegister = kPORT_UnlockRegister};
    /* PORT0_16 (pin 83) is configured as LPI2C0_SDA */
    PORT_SetPinConfig(PORT0, 16U, &port0_16_pin83_config);

const port_pin_config_t port0_17_pin84_config = {/* Internal pull-up resistor is enabled */
                                                     .pullSelect = kPORT_PullUp,
                                                     /* Low internal pull resistor value is selected. */
                                                     .pullValueSelect = kPORT_LowPullResistor,
                                                     /* Fast slew rate is configured */
                                                     .slewRate = kPORT_FastSlewRate,
                                                     /* Passive input filter is disabled */
                                                     .passiveFilterEnable = kPORT_PassiveFilterDisable,
                                                     /* Open drain output is disabled */
                                                     .openDrainEnable = kPORT_OpenDrainDisable,
                                                     /* Low drive strength is configured */
                                                     .driveStrength = kPORT_LowDriveStrength,
                                                     /* Normal drive strength is configured */
                                                     .driveStrength1 = kPORT_NormalDriveStrength,
                                                     /* Pin is configured as LPI2C0_SCL */
                                                     .mux = kPORT_MuxAlt2,
                                                     /* Digital input enabled */
                                                     .inputBuffer = kPORT_InputBufferEnable,
                                                     /* Digital input is not inverted */
                                                     .invertInput = kPORT_InputNormal,
                                                     /* Pin Control Register fields [15:0] are not locked */
                                                     .lockRegister = kPORT_UnlockRegister};
    /* PORT0_17 (pin 84) is configured as LPI2C0_SCL */
    PORT_SetPinConfig(PORT0, 17U, &port0_17_pin84_config);

~~~

# 生成工程

~~~c
scons --target=mdk5
~~~

# 示例代码

* 不使用sensor框架

~~~c
#include "P3T1755.h"
static void p3t1755_test(int argc, char *argv[])
{
    p3t1755_init();
    float temp = 0;
    if (p3t1755_read_temp(&temp) == RT_EOK)
    {
        rt_kprintf("temp:%.2f\n", temp);
    }
}
MSH_CMD_EXPORT(p3t1755_test, i2c p3t1755 sample);
~~~

* 使用sensor 框架

使能sensor框架

![PixPin_2025-02-26_09-55-39](https://cdn.jsdelivr.net/gh/CYFS3/Typroa/202502261024786.png)

~~~c
#include "nxp_p3t1755_sensor_v2.h"
static void p3t1755_sensor_test(void)
{
    rt_device_t dev;
    struct rt_sensor_data data;
    struct rt_sensor_config config;
    rt_hw_p3t1755_init("p3t1755",&config);
    /* 查找传感器设备 */
    dev = rt_device_find("tm-p3t1755");
    /* 以只读及轮询模式打开传感器设备 */
    rt_device_open(dev, RT_DEVICE_FLAG_RDONLY);

if (rt_device_read(dev, 0, &data, 1) == 1)
    {
        rt_kprintf("temp: %.3f, timestamp:%5d\n", data.data.temp, data.timestamp);
    }
    rt_device_close(dev);

}

MSH_CMD_EXPORT(p3t1755_sensor_test, p3t1755 sensor test);
~~~

# 运行结果

![](https://cdn.jsdelivr.net/gh/CYFS3/Typroa/202502261024787.png)

使用sensor框架

![PixPin_2025-02-26_10-15-48](https://cdn.jsdelivr.net/gh/CYFS3/Typroa/202502261024788.png)