本程序配合上位机软件可以通过串口下载字模数据到单片机外接RAM中。达到随时改变点阵屏显示内容的目的 外接RAM为6264大小为8K， 6264外接3。6V的备用电池来提供数据备份功能。-This procedure with the PC software can be downloaded through the serial data to a matrix of single-chip external RAM. Reached at any time to change the do