关于LM3S的EPI 通用模式数据读取！

lingqian chan

接触EPI时间不多，遇到一些问题。采用通用8位数据模式与CPLD进行高速数据传输，只需要读取CPLD的数据。以下是初始化代码：

//系统时钟100MHZ

SysCtlClockSet(SYSCTL_SYSDIV_2| SYSCTL_USE_PLL | SYSCTL_XTAL_16MHZ |
SYSCTL_OSC_MAIN);

//使能各IO
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOC);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOD);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOG);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOH);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOJ);

//设置IO口功能
GPIOPinConfigure(GPIO_PH3_EPI0S0);
GPIOPinConfigure(GPIO_PH2_EPI0S1);
GPIOPinConfigure(GPIO_PC4_EPI0S2);
GPIOPinConfigure(GPIO_PC5_EPI0S3);
GPIOPinConfigure(GPIO_PC6_EPI0S4);
GPIOPinConfigure(GPIO_PC7_EPI0S5);
GPIOPinConfigure(GPIO_PH0_EPI0S6);
GPIOPinConfigure(GPIO_PH1_EPI0S7);
GPIOPinConfigure(GPIO_PJ4_EPI0S28);
GPIOPinConfigure(GPIO_PJ5_EPI0S29);
GPIOPinConfigure(GPIO_PJ6_EPI0S30);
GPIOPinConfigure(GPIO_PG7_EPI0S31);
GPIOPinConfigure(GPIO_PF2_LED1);
GPIOPinConfigure(GPIO_PF3_LED0);

//使能EPI模块
SysCtlPeripheralEnable(SYSCTL_PERIPH_EPI0);

GPIOPadConfigSet(GPIO_PORTC_BASE,EPI_PORTC_PINS,GPIO_STRENGTH_8MA,GPIO_PIN_TYPE_STD_WPD);
GPIOPadConfigSet(GPIO_PORTH_BASE,EPI_PORTH_PINS,GPIO_STRENGTH_8MA,GPIO_PIN_TYPE_STD_WPD);
GPIOPadConfigSet(GPIO_PORTJ_BASE,EPI_PORTJ_PINS,GPIO_STRENGTH_8MA,GPIO_PIN_TYPE_STD_WPD);
GPIOPadConfigSet(GPIO_PORTG_BASE,GPIO_PIN_7,GPIO_STRENGTH_8MA,GPIO_PIN_TYPE_STD_WPD);

GPIODirModeSet(GPIO_PORTC_BASE,EPI_PORTC_PINS,GPIO_DIR_MODE_HW);
GPIODirModeSet(GPIO_PORTH_BASE,EPI_PORTH_PINS,GPIO_DIR_MODE_HW);
GPIODirModeSet(GPIO_PORTJ_BASE,EPI_PORTJ_PINS,GPIO_DIR_MODE_HW);
GPIODirModeSet(GPIO_PORTG_BASE,GPIO_PIN_7,GPIO_DIR_MODE_HW);

EPIDividerSet(EPI0_BASE,1); //EPI时钟为系统时钟的1/2
EPIModeSet(EPI0_BASE,EPI_MODE_GENERAL); //通用模式

while(HWREG(EPI0_BASE + EPI_O_STAT) & EPI_STAT_INITSEQ)
{
}

EPIFIFOConfig(EPI0_BASE,EPI_FIFO_CONFIG_RX_FULL);   //设置FIFO满中断
EPIIntRegister(EPI0_BASE,EpiIntHander);                                   //注册中断函数
EPINonBlockingReadConfigure(EPI0_BASE,0,EPI_NBCONFIG_SIZE_8,0);   //非阻塞读取设置，8位数据
EPIIntEnable(EPI0_BASE,EPI_INT_RXREQ); //开启EPI RX FIFO 中断

IntMasterEnable(); //使能总中断

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

关于之后的数据读取是如何进行的？

EPINonBlockingReadGet8(EPI0_BASE,ulCount,pucBuf);如何使用？看手册ulCount <4096 ，可是8字节的NBRFIFO ，如何读取大于NBRFIFO的数据？

12 年多前

0 Teddy Liu 12 年多前

TI__Intellectual 1155 points

1,首先系统时钟只能为80MHz， SysCtlClockSet(SYSCTL_SYSDIV_2_5| SYSCTL_USE_PLL | SYSCTL_XTAL_16MHZ |
SYSCTL_OSC_MAIN);

2,example:

#include <string.h>
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "inc/hw_ints.h"
#include "inc/hw_sysctl.h"
#include "driverlib/epi.h"
#include "driverlib/flash.h"
#include "driverlib/gpio.h"
#include "driverlib/interrupt.h"
#include "driverlib/rom.h"
#include "driverlib/rom_map.h"
#include "driverlib/sysctl.h"
#include "driverlib/systick.h"

#include "inc/hw_gpio.h"

#define SRAM_MEM_SIZE 0x00100000 //Size in bytes (1MByte)

#define AUTO_CS 1

#define EXT_SRAM_BASE 0x68000000

//*****************************************************************************
//
// Use the following to specify the GPIO pins used by the EPI bus (EPI0S00
// through EPI0S19 and EPI0S28 through EPI0S31). These basic definitions
// set up the pins required for the SRAM daughter board.
//
//*****************************************************************************

#define EPI_PORTA_PINS          0x00
#define EPI_PORTB_PINS          0x00
#define EPI_PORTC_PINS          0xf0
#define EPI_PORTD_PINS          0xf0
#define EPI_PORTE_PINS          0x03
#define EPI_PORTF_PINS          0x80
#define EPI_PORTG_PINS          0x13
#define EPI_PORTH_PINS          0xBF
#define EPI_PORTJ_PINS          0x07

void GpioPinSet(void)
{
    //
    // The EPI0 peripheral must be enabled for use.
    // Ê¹ÄÜEPI½Ó¿Ú
    SysCtlPeripheralEnable(SYSCTL_PERIPH_EPI0);
    //
    // Ê¹ÄÜ¸÷¸öÊ¹ÓÃµÄIO¿Ú
    //
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOC);
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOD);
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE);
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOG);
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOH);
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOJ);
    GPIOPinConfigure(GPIO_PB6_C0O );
    GPIOPinConfigure(GPIO_PH2_EPI0S1);
    GPIOPinConfigure(GPIO_PC4_EPI0S2);
    GPIOPinConfigure(GPIO_PC5_EPI0S3);
    GPIOPinConfigure(GPIO_PC6_EPI0S4);
    GPIOPinConfigure(GPIO_PC7_EPI0S5);
    GPIOPinConfigure(GPIO_PH0_EPI0S6);
    GPIOPinConfigure(GPIO_PH1_EPI0S7);
    GPIOPinConfigure(GPIO_PE0_EPI0S8);
    GPIOPinConfigure(GPIO_PE1_EPI0S9);
    GPIOPinConfigure(GPIO_PH4_EPI0S10);
    GPIOPinConfigure(GPIO_PH5_EPI0S11);
    GPIOPinConfigure(GPIO_PF7_EPI0S12);
    GPIOPinConfigure(GPIO_PG0_EPI0S13);
    GPIOPinConfigure(GPIO_PG1_EPI0S14);
    GPIOPinConfigure(GPIO_PG4_EPI0S15);
    GPIOPinConfigure(GPIO_PJ0_EPI0S16);
    GPIOPinConfigure(GPIO_PJ1_EPI0S17);
    GPIOPinConfigure(GPIO_PJ2_EPI0S18);
    GPIOPinConfigure(GPIO_PD4_EPI0S19);
//    GPIOPinConfigure(GPIO_PD2_EPI0S20);
//    GPIOPinConfigure(GPIO_PD3_EPI0S21);
//    GPIOPinConfigure(GPIO_PB5_EPI0S22);
//    GPIOPinConfigure(GPIO_PB4_EPI0S23);
//    GPIOPinConfigure(GPIO_PE2_EPI0S24);
//    GPIOPinConfigure(GPIO_PE3_EPI0S25);
    GPIOPinConfigure(GPIO_PH7_EPI0S27);
    GPIOPinConfigure(GPIO_PD5_EPI0S28);
    GPIOPinConfigure(GPIO_PD6_EPI0S29);
    GPIOPinConfigure(GPIO_PD7_EPI0S30);
//    GPIOPinConfigure(GPIO_PG7_EPI0S31);
    //
    // Configure the GPIO pins for EPI mode. All the EPI pins require 8mA
    // drive strength in push-pull operation. This step also gives control of
    // pins to the EPI module.
    //
    GPIOPinTypeEPI(GPIO_PORTB_BASE, EPI_PORTB_PINS);
    GPIOPinTypeEPI(GPIO_PORTC_BASE, EPI_PORTC_PINS);
    GPIOPinTypeEPI(GPIO_PORTD_BASE, EPI_PORTD_PINS);
    GPIOPinTypeEPI(GPIO_PORTE_BASE, EPI_PORTE_PINS);
    GPIOPinTypeEPI(GPIO_PORTF_BASE, EPI_PORTF_PINS);
    GPIOPinTypeEPI(GPIO_PORTG_BASE, EPI_PORTG_PINS);
    GPIOPinTypeEPI(GPIO_PORTH_BASE, EPI_PORTH_PINS);
    GPIOPinTypeEPI(GPIO_PORTJ_BASE, EPI_PORTJ_PINS);
    //
    // Sets the clock divider for the EPI module. In this case set the
    // divider to 0, making the EPIClock = SysClk.
    EPIDividerSet(EPI0_BASE, 10);
    //
    // Sets the usage mode of the EPI module. EPI_MODE_HB8
    //
    EPIModeSet(EPI0_BASE, EPI_MODE_HB8);
    // set
    // Ê¹ÓÃÏàÍ¬²¨ÌØÂÊµØÖ·Êý¾Ý²»¸´ÓÃ csÐÅºÅ ×Ö½Ú¶ÁÈ¡
//    EPIConfigHB8Set(EPI0_BASE, EPI_HB8_MODE_ADDEMUX | EPI_HB8_WRWAIT_1
//                               | EPI_HB8_RDWAIT_1 | EPI_HB8_CSCFG_CS, 0);

    EPIConfigHB8Set(EPI0_BASE, EPI_HB8_MODE_ADDEMUX | EPI_HB8_WRWAIT_1
                               | EPI_HB8_RDWAIT_1 | EPI_HB8_WRHIGH
                               | EPI_HB8_RDHIGH | EPI_HB8_CSCFG_DUAL_CS, 5);

//Õâ¸öµØ·½½øÐÐ¸ÄRD/WRÐÅºÅµÄ¼«ÐÔ

    //VPC3Ó³Éäµ½Æ¬ÍâÍâÉè£¬µØÖ·Îª0ååxA000 0000£¬´óÐ¡Îª64K
    //Ë«¿ÚRAMÓ³Éäµ½Æ¬ÍâRAM,EPÆ¬ÍâÍâÉè,´óÐ¡Îª64k£¬µØÖ·0x6000 0000

    EPIAddressMapSet(EPI0_BASE, EPI_ADDR_PER_SIZE_256B | EPI_ADDR_PER_BASE_A | EPI_ADDR_RAM_SIZE_64KB | EPI_ADDR_RAM_BASE_6);
//    EPIAddressMapSet(EPI0_BASE, EPI_ADDR_PER_SIZE_256B | EPI_ADDR_PER_BASE_A);
}

int main(void)
{
int *dpointer;
//
    // Set the system clock to run at 80MHz from the PLL
    //
    SysCtlClockSet(SYSCTL_SYSDIV_2_5| SYSCTL_USE_PLL | SYSCTL_OSC_MAIN |
                       SYSCTL_XTAL_16MHZ);

    //
    // Set the device pinout appropriately for this board. This also enables
    // all the GPIO ports required.
    //
    //PinoutSet();
GpioPinSet();
while(1){
    HWREGB(EXT_SRAM_BASE + 0xAAA) = 0x55;

*dpointer= HWREGB(EXT_SRAM_BASE + 0xAAA);

}
while(1);

}

存档论坛

基于 Stellaris®︎ ARM®︎ Cortex™︎-M3 的 MCU (Read-Only)

关于LM3S的EPI 通用模式数据读取！