一.12864液晶在出厂时其对比度已经调好，所以用户在使用的时候第三管脚可不用接任何东西，本实验板上为了兼容多家12864液晶所以加了液晶对比度调节电位器，



若用户使用我们配套的12864液晶可不用管它，液晶的第三管脚悬空就可以。



有些液晶功耗比较大，用户在使用的时候可将液晶的第19、20引脚的背光不接，这样字体会很清楚。



二.在使用USB-ISP下载器供电时,由于下载器输出电压为4.3V.电压偏低,字体显示较不清楚,建议另接上USB或者外接独立电源供电.-1 .12864 LCD contrast has been at the factory of its fine, when in use so the user can not access the third pin anything, this experiment is compatible with more than 12864 on-board LCD so in order to increase the LCD contrast adjustment potentiometer, if the user Use our supporting 12864 LCD can not ignore it, LCD' s third pin can be left vacant. Some of the larger LCD power consumption, the user can be in use when the first 19,20-pin LCD backlight will not answer, so that fonts will be very clear. 2. In the use of USB-ISP downloader power, due to download the output voltage is 4.3V. Voltage is low, the font displays are less clear, the proposed independence of the other connected to the USB or external power supply.