基于DSP的大尺寸液晶屏驱动方法的研究

Method of Driving Large-size LCD Screen Based on DSP

介绍了DSP驱动T6963C内核液晶屏的原理,给出了汉字和字符混合显示的方法。分析了限制液晶屏刷新速率的原因。针对C语言开发环境下,DSP驱动大尺寸液晶屏显示刷新速率较慢的问题,提出了几种实用的软件改进方法:把C语言和汇编语言相结合提高字库点阵提取速度及液晶屏的数据传输速度;增设页面缓存,采用自动写入方式传送,减少发送的命令数;同时,摒弃了低分辨率下常用的屏幕点阵填写模式,采用与PC机中高速二级缓存Cache命中技术相类似的索引码进行显示等。实验证明,经改进后,刷新全屏的平均时间由原来的2s减少到0.5s,提高了液晶屏的显示效果。

Driving LCD module with T6963C kernel by DSP was introduced. The reason of limiting LCD refresh speed was analyzed. The method of displaying Chinese characters mixed with ASCII was given. In order to improve the speed of driving large-size LCD screen developed by C language, several applied software methods were put forward： Combining C language with assembly language to improve the speed of getting pixels and the speed of data transfer of LCD screen; Adding memory pages and adopting automatic writing mode to decrease the number of commands; instead of the pixel filled mode under the low-resolution, index code resembled L2 Cache of PC was used. The average refresh time has decreased from 2 s to 0.5 s, so the display effect of LCD is improved.