http://www.openedv.com/posts/list/22181.htm
上面网址是在论坛上找到的串口数据绘图的软件，但是没弄明白怎么用，请各位大神指点，按照如下代码试了一下，想输出个直线，不能用，谢谢
printf("ch1 is %d ",0x55);
printf("ch1 is %d ",0x51);
printf("ch1 is %d ",255);
printf("ch1 is %d ",255);                         
printf("ch1 is %d ",255);
printf("ch1 is %d ",255);       
printf("ch1 is %d ",255);
printf("ch1 is %d ",255);       
printf("ch1 is %s ",sum);