本文來(lái)源電子發(fā)燒友社區(qū)，作者：李先生， 帖子地址：https://bbs.elecfans.com/jishu_2303741_1_1.html


準(zhǔn)備

參考https://bbs.elecfans.com/jishu_2303737_1_1.html的ssh登錄配置等。

apt install lrzsz安裝sz rz工具

rz是導(dǎo)入文件到開(kāi)發(fā)板

sz相反

安裝后,crt中ssh登錄開(kāi)發(fā)板后,就可以輸入rz回車

自動(dòng)彈出選擇文件對(duì)話框選擇文件,點(diǎn)擊Add點(diǎn)擊Ok就可發(fā)送到開(kāi)發(fā)板

sz 文件名

則從開(kāi)發(fā)板下載到本地

輸出的路徑可以配置

右鍵點(diǎn)擊連接->Session Options...

配置上傳下載路徑如下

Framebuffer測(cè)試代碼

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

int main(int argc, char *argv[])

{

int fd = -1;

int ret = -1;

uint8_t *p_fb = 0;

struct fb_fix_screeninfo finfo;

struct fb_var_screeninfo vinfo;

memset(&finfo,0,sizeof(finfo));

memset(&vinfo,0,sizeof(vinfo));

fd = open(argv[1],O_RDWR);

if(fd < 0)

{

fprintf(stderr,"open %s err, %sn",argv[1],strerror(errno));

return -1;


}

ret = ioctl(fd, FBIOGET_FSCREENINFO, &finfo);

if(ret < 0)

{

fprintf(stderr,"ioctl finfo err, %sn",strerror(errno));

close(fd);

return -1;



}

ret = ioctl(fd, FBIOGET_VSCREENINFO, &vinfo);

if(ret < 0)

{

fprintf(stderr,"ioctl vinfo err, %sn",strerror(errno));

close(fd);

return -1;

}

unsigned long len = vinfo.xres_virtual  * vinfo.yres_virtual * vinfo.bits_per_pixel / 8;

p_fb = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);

if(p_fb == NULL)

{

fprintf(stderr,"mmap len %ld errn",len);

close(fd);

return -1;

}

fprintf(stderr,"x = %d y = %d bits = %d len = %ldn",vinfo.xres_virtual,vinfo.yres_virtual,vinfo.bits_per_pixel,len);

volatile int times = 30;

while(times--)

{

if(vinfo.bits_per_pixel == 16)

{

for(unsigned int i=0; i< len/2; )

{

*((uint16_t*)(p_fb + i)) = 0xF800;

i+=2;


}

usleep(atoi(argv[2])*1000);

for(unsigned int i=0; i< len/2;)

{

*((uint16_t*)(p_fb + i)) = 0x07E0;

i+=2;


}

usleep(atoi(argv[2])*1000);

for(unsigned int i=0; i< len/2;)

{

*((uint16_t*)(p_fb + i)) = 0x001F;

i+=2;

}

usleep(atoi(argv[2])*1000);


}

else

{

for(unsigned int i=0; i< len/4; )

{


*((uint32_t*)(p_fb + i)) = 0xFF0000;

i+=4;

}

usleep(atoi(argv[2])*1000);

for(unsigned int i=0; i< len/4;)

{

*((uint32_t*)(p_fb + i)) = 0x00FF00;

i+=4;


}

usleep(atoi(argv[2])*1000);

for(unsigned int i=0; i< len/4;)

{

*((uint32_t*)(p_fb + i)) = 0x0000FF;

i+=4;


}

usleep(atoi(argv[2])*1000);


}


}

munmap(p_fb,len);

close(fd);

return 0;


}

rz導(dǎo)入到開(kāi)發(fā)板

編譯

gcc framebuffer.c -o framebuffer

運(yùn)行

./framebuffer /dev/fb0 200

可以看到以200ms間隔 rgb刷屏 30次。

總結(jié)

測(cè)試framebuffer和hdmi顯示ok，后續(xù)就可以基于此進(jìn)行相應(yīng)的圖形程序的開(kāi)發(fā)。

比如移植lvgl等。