我正在尝试将我的十六进制输出向左移动一位，以便我可以在 7 段液晶显示器上显示 9 以上的数字。
在 C 语言上编程，我使用的软件是 NIOS II，所以我可以直接在 DE0 板上重新编程。
该项目的目的是每次按下“button1”时将 LCD 的值增加 1。我已经成功地做到了这一点，但是当然在 9 点之后它需要向左移动并从 1 重新开始，用 0 替换它来自的位置。我做了一些研究，但没有任何运气所以任何帮助表示赞赏。谢谢。
代码如下：
#include "sys/alt_stdio.h" //for the alt_putstr function below. Outputs to Eclipse console
#include "altera_avalon_pio_regs.h" //for the I/O functions in the while loop below
#include "sys/alt_timestamp.h" //see Nios II Software Developer’s Handbook, Timestamp Driver
#include "system.h"
#define setHeaderOuts HEADEROUTPUTS_BASE+0x10 //HEADEROUTPUTS_BASE is defined in system.h of the _bsp file. It refers to the base address in the Qsys design
//the hex offset (in this case 0x10, which is 16 in decimal) gives the number of bytes of offset
//each register is 32 bits, or 4 bytes
//so to shift to register 4, which is the outset register, we need 4 * (4 bytes) = 16 bytes
#define clearHeaderOuts HEADEROUTPUTS_BASE+0x14 //to shift to register 5 (the 'outclear' register) we need to shift by 5 * (4 bytes) = 20 bytes, (=0x14 bytes)
// offset of 5 corresponds to the 'outclear' register of the PIO.
int main(void)
{
alt_putstr("This is the ELEE1062 version of the NIOS processor");
int buttons = 0; //the buttons on the DE0
//int switches = 0; //the switches on the DE0
int count = 0; //general purpose counter
int hexd = 0;
while(1)
{
buttons=IORD_ALTERA_AVALON_PIO_DATA(PUSHBUTTONS1_2_BASE); //read the value of the pushbuttons
while((buttons & 0x01) == 1) // i.e. while pushbutton 1 is not pressed
{
buttons=IORD_ALTERA_AVALON_PIO_DATA(PUSHBUTTONS1_2_BASE); //read the value of the pushbuttons
}
count=count+1;
IOWR_ALTERA_AVALON_PIO_DATA(DE0_LEDS_BASE,count); //display the value of count in binary, using the green LEDs
while((buttons & 0x01) == 0) //i.e. while pushbutton 1 is pressed
{
buttons=IORD_ALTERA_AVALON_PIO_DATA(PUSHBUTTONS1_2_BASE); //read the value of the pushbuttons
}
if (count==0)
{
hexd=0x000000c0;
}
else if (count==1)
{
hexd=0xf9;
}
else if ( count==2)
{
hexd=0xa4;
}
else if ( count==3)
{
hexd=0xb0;
}
else if ( count==4)
{
hexd=0x99;
}
else if ( count==5)
{
hexd=0x92;
}
else if ( count==6)
{
hexd=0x82;
}
else if ( count==7)
{
hexd=0xd8;
}
else if ( count==8)
{
hexd=0x80;
}
else if ( count==9)
{
hexd=0x90;
}
else if ( count>9)
{
hexd= hexd & ~(1<<count);
}
//count=alt_timestamp_start(); //start the timer. Timer increments each clock cycle. Clock for ELEE1062_NIOS is 50MHz
//buttons=IORD_ALTERA_AVALON_PIO_DATA(PUSHBUTTONS1_2_BASE); //read the value of the pushbuttons
//switches=IORD_ALTERA_AVALON_PIO_DATA(DE0SWITCHES_BASE); //read the value of the switches
IOWR_ALTERA_AVALON_PIO_DATA(SSEG_BASE,hexd); //DE0 7 segment displays all off --notice that a logic '1' turns the segment off
IOWR_ALTERA_AVALON_PIO_DATA(SSEG_BASE,hexd); //DE0 7 segment displays all on
IOWR_ALTERA_AVALON_PIO_DATA(DE0_LEDS_BASE,0x000); //all off --for the green LEDs, a logic '0' turns the LED off
IOWR_ALTERA_AVALON_PIO_DATA(DE0_LEDS_BASE,0xfff); //all on
IOWR_ALTERA_AVALON_PIO_DATA(clearHeaderOuts,0x01); //turn off the first pin of the output port
IOWR_ALTERA_AVALON_PIO_DATA(setHeaderOuts,0x01); //turn on the first pin of the output port
//IOWR_ALTERA_AVALON_PIO_DATA(SSEG_BASE,switches); //light up the 7 segment display segments corresponding to how the DE0 switches are set
IOWR_ALTERA_AVALON_PIO_DATA(DE0_LEDS_BASE,buttons); //light up the green LEDs corresponding to which DE0 buttons are pushed
//count=alt_timestamp(); //record the value of the timer, and store in the 'count' variable
}
}