学习KEA之GPIO
GPIO简介
KEA系列的GPIO有三个GPIO口： GPIOA、GPIOB和GPIOC， 每个GPIO口又包括了32个GPIO引脚:
GPIO配置步骤
配置输入
- Clear the corresponding bit in the port data direction register (GPIOx_PDDR).
- Enable the pin as input, by clearing the corresponding bit in port input disable register (GPIOx_PIDR).
- Enable internal pullup resistor if necessary, by setting the corresponding bit in port pullup enable register(PORT_PUEx).
配置输出
- Set the corresponding bit in port data direction register (GPIOx_PDDR).
- Disable the pin as input, by setting the corresponding bit in port input disable register (GPIOx_PIDR). All pins disable the input by default after reset.
输出高电平
• Set the corresponding bit in port set output register (GPIOx_PSOR)
输出低电平
• Set the corresponding bit in port clear output register (GPIOx_PCOR)
输出反转电平
• Set the corresponding bit in port toggle output register (GPIOx_PTOR)
GPIO库函数
我们之前写过一篇文章：使用S32DS来开发KEA并配有LED闪烁的例程， 这里面就已经讲到GPIO了，并且推荐使用S32DS使用库函数版本来开发。使用库函数的最大便利是不用看手册，极大地提高了开发效率，使我们更多时间来开发应用 。
使用GPIO库函数的，你可以：
- 配置GPIO是输入还是输出
- 配置内部上拉电阻
- 对输出进行反转、置1、清0
- 读取输入
我们新建S32DS工程后，已经包括了库函数，直接在源文件中引用GPIO头文件就可以了，具体内容请看附录：
#include "gpio.h"
配置GPIO
- CONFIG_PIN_AS_GPIO(port,port_pin,mode) /* 配置GPIO为输入或输出 */
- ENABLE_INPUT(port,port_pin) /* 允许输入 */
- DISABLE_INPUT(port,port_pin) /* 禁止输入 */
- ENABLE_PULLUP(port,port_pin) /* 配置内部上拉电阻 */
使用GPIO
- OUTPUT_SET(port,port_pin) /* 输出高电平 */
- OUTPUT_CLEAR(port,port_pin) /* 输出低电平 */
- OUTPUT_TOGGLE(port,port_pin) /* 反转输出电平*/
- READ_INPUT(port,port_pin) /* 读取GPIO电平 */
注： 其中上面的
port可以是：PTA, TB, PTC, PTD, PTE, PTF, PTG, PTH, PTI;mode可以是:OUTPUT或 INPUT;port_pin比较多，类似PTD2
GPIO例程
这里还是直接贴上以前的例程:
/*
* SKEAZN64, LED0连接PTD2，高电平亮，低电平不亮
*/
#include "derivative.h" /* include peripheral declarations SSKEAZN64M2 */
#include "gpio.h" /* GPIO库函数 */
void Delay(void);
int main(void)
{
CONFIG_PIN_AS_GPIO(PTD, PTD2, OUTPUT); /* Config LED0 as output */
OUTPUT_CLEAR(PTD, PTD2);
for( ; ;)
{
OUTPUT_SET(PTD, PTD2); /* Turn on LED0*/
Delay();
OUTPUT_CLEAR(PTD, PTD2); /* Turn off LED0*/
Delay();
}
/* to avoid the warning message for GHS: statement is unreachable*/
#if defined (__ghs__)
#pragma ghs nowarning 111
#endif
#if defined (__ICCARM__)
#pragma diag_suppress=Pe111
#endif
return 0;
}
/*
* 延时大概是400ms
*/
void Delay(void)
{
uint32_t i,j;
for(i=0; i<8; i++)
for(j=0; j<65535; j++);
}
小结
选择库函数来开发KEA的GPIO是比较使便利的。
最后说一个坑，S32DS没有KEA8系列的SDK，只得使用寄存器版本：
在这里插入图片描述：
附录
gpio.h头文件：
/******************************************************************************
*
* Freescale Semiconductor Inc.
* (c) Copyright 2013 Freescale Semiconductor, Inc.
* ALL RIGHTS RESERVED.
*
***************************************************************************
*
* THIS SOFTWARE IS PROVIDED BY FREESCALE "AS IS" AND ANY EXPRESSED OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL FREESCALE OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*
***************************************************************************//*!
*
* @file GPIO.h
*
* @author Freescale
*
* @brief provide common GPIO utilities.
*
*******************************************************************************/
#ifndef GPIO_H_
#define GPIO_H_
/*******************************************************************************
* Includes
*******************************************************************************/
#include "derivative.h"
/*******************************************************************************
* Constants
********************************************************************************/
/*******************************************************************************
* Macros
********************************************************************************/
/***********************************************************
*
* Ports mapped to GPIOA,GPIOB and GPIOC registers
*
**********************************************************/
#if defined(MCU_SKEAZ1284)
#define PTA GPIOA_BASE_PTR
#elif defined(MCU_SKEAZN642)
#define PTA GPIOA //PTA defined in defice header as GPIOA. Not a problem since GPIOA=GPIOA_BASE_PTR
#else
/* Define PTA for your device. */
#endif
#define PTB GPIOA_BASE_PTR
#define PTC GPIOA_BASE_PTR
#define PTD GPIOA_BASE_PTR
#define PTE GPIOB_BASE_PTR
#define PTF GPIOB_BASE_PTR
#define PTG GPIOB_BASE_PTR
#define PTH GPIOB_BASE_PTR
#if defined(MCU_SKEAZ1284)
#define PTI GPIOC_BASE_PTR
#elif defined(MCU_SKEAZN642)
/* KEAZN64 has no PTI. */
#else
/* If your device has more ports, define them here. */
#endif
/***********************************************************
*
* Input/Output macro
*
**********************************************************/
#define OUTPUT 1
#define INPUT 0
/***********************************************************
*
* GPIO configuration macro
*
**********************************************************/
#define CONFIG_PIN_AS_GPIO(port,port_pin,mode) XCONFIG_PIN_AS_GPIO(port,port_pin,mode)
#define XCONFIG_PIN_AS_GPIO(port,port_pin,mode) (mode == 0) ? (port->PDDR &=~(1<< port_pin)) : (port->PDDR |= (1 << port_pin))
/***********************************************************
*
* Enable and Disable input macro
*
**********************************************************/
#define ENABLE_INPUT(port,port_pin) XENABLE_INPUT(port,port_pin)
#define XENABLE_INPUT(port,port_pin) port->PIDR &=~ (1<
#define DISABLE_INPUT(port,port_pin) XDISABLE_INPUT(port,port_pin)
#define XDISABLE_INPUT(port,port_pin) port->PIDR |= (1<
/***********************************************************
*
* Enable and Disable pullup resistor macro
*
**********************************************************/
#define ENABLE_PULLUP(port,port_pin) XENABLE_PULLUP(port,port_pin)
#if defined(MCU_SKEAZ1284)
#define XENABLE_PULLUP(port,port_pin) if(port==GPIOA_BASE_PTR){PORT_BASE_PTR->PUE0 |= (1<PUE1|=(1<PUE2|=(1<
#elif defined(MCU_SKEAZN642)
#define XENABLE_PULLUP(port,port_pin) if(port==GPIOA_BASE_PTR){PORT_BASE_PTR->PUE0 |= (1<PUE1|=(1<
#else
/* Implement this function for your device. */
#endif
#define DISABLE_PULLUP(port,port_pin) XDISABLE_PULLUP(port,port_pin)
#if defined(MCU_SKEAZ1284)
#define XDISABLE_PULLUP(port,port_pin) if(port==GPIOA_BASE_PTR){PORT_BASE_PTR->PUE0 &=~ (1<PUE1 &=~ (1<PUE2 &=~(1<
#elif defined(MCU_SKEAZN642)
#define XDISABLE_PULLUP(port,port_pin) if(port==GPIOA_BASE_PTR){PORT_BASE_PTR->PUE0 &=~ (1<PUE1 &=~ (1<
#else
/* Implement this function for your device. */
#endif
/***********************************************************
*
* Output set macro
*
**********************************************************/
#define OUTPUT_SET(port,port_pin) XOUTPUT_SET(port,port_pin)
#define XOUTPUT_SET(port,port_pin) port->PSOR |=(1<
/***********************************************************
*
* Output clear macro
*
**********************************************************/
#define OUTPUT_CLEAR(port,port_pin) XOUTPUT_CLEAR(port,port_pin)
#define XOUTPUT_CLEAR(port,port_pin) port->PCOR |=(1<
/***********************************************************
*
* Output toggle macro
*
**********************************************************/
#define OUTPUT_TOGGLE(port,port_pin) XOUTPUT_TOGGLE(port,port_pin)
#define XOUTPUT_TOGGLE(port,port_pin) port->PTOR |=(1<
/***********************************************************
*
* Read input macro
*
**********************************************************/
#define READ_INPUT(port,port_pin) XREAD_INPUT(port,port_pin)
#define XREAD_INPUT(port,port_pin) (port->PDIR & GPIO_PDIR_PDI(1<
/*******************************************************************************
* Types
********************************************************************************/
/*******************************************************************************
* Variables
********************************************************************************/
/*******************************************************************************
* Global Variables
********************************************************************************/
/***********************************************************
*
* Pins mapped to GPIOA,GPIOB and GPIOC register numbers
*
**********************************************************/
enum GPIOA_Register {
PTA0,
PTA1,
PTA2,
PTA3,
PTA4,
PTA5,
PTA6,
PTA7,
PTB0,
PTB1,
PTB2,
PTB3,
PTB4,
PTB5,
PTB6,
PTB7,
PTC0,
PTC1,
PTC2,
PTC3,
PTC4,
PTC5,
PTC6,
PTC7,
PTD0,
PTD1,
PTD2,
PTD3,
PTD4,
PTD5,
PTD6,
PTD7,
};
enum GPIOB_Register {
PTE0,
PTE1,
PTE2,
PTE3,
PTE4,
PTE5,
PTE6,
PTE7,
PTF0,
PTF1,
PTF2,
PTF3,
PTF4,
PTF5,
PTF6,
PTF7,
PTG0,
PTG1,
PTG2,
PTG3,
#if defined(MCU_SKEAZ1284)
PTG4,
PTG5,
PTG6,
PTG7,
PTH0,
#elif defined(MCU_SKEAZN642)
/* KEAZN642 does not implement the incapsulated pins. */
PTH0=24,
#else
/* List the pins that your device uses. */
#endif
PTH1,
PTH2,
#if defined(MCU_SKEAZ1284)
PTH3,
PTH4,
PTH5,
PTH6,
#elif defined(MCU_SKEAZN642)
PTH6=30,
#else
/* List the pins that your device uses. */
#endif
PTH7,
};
#if defined(MCU_SKEAZ1284)
enum GPIOC_Register {
PTI0,
PTI1,
PTI2,
PTI3,
PTI4,
PTI5,
PTI6,
};
#elif defined(MCU_SKEAZN642)
/* There is no GPIOC register in KEAZN64 because there is no PTI. */
#else
/* List any additional pins your device may use here. */
#endif
/*******************************************************************************
* Global Functions
********************************************************************************/
#endif /* GPIO_H_ */