Article 11: Display Module 12864 LCD
The previous article discussed the use of the 1602 LCD module, which is very easy to use but has the drawback of only displaying characters and not supporting Chinese or more complex graphics. In this article, we will explore the 12864 LCD module.
The 12864 refers to the resolution of this LCD screen, which is 128*64. This LCD is very classic. Of course, since there is a 12864, there will also be various other resolutions such as 128*32, 320*240, etc. However, for simplicity, we will only play with the 12864 LCD that has built-in library functions in Mixly.
1. Character Display of 12864 LCD
Actually, there are many types of 12864 LCD modules; the one below is the yellow-green screen that I used frequently before.
This screen has 8 pins on the back (the last four are not used to drive the screen but to read the font library; of course, the one you buy may not come with a font library, in which case those four pins will be useless).
The program for this screen is in the second program block of the Mixly display module (as shown below).
After dragging the program block into the programming area, we need to modify the module model in the initialization to LCM12864, and fill in the pin numbers for CS, DC, and RST as we like; I filled in 12, 13, and 14 here.
Then drag a page1 function block out, and the final program is as shown below:
Now we start wiring according to the pin numbers we filled in the program block:
LCD12864 ESP32
CS —————- 12
RST —————- 14
RS （DC）———- 13
SDA （MOSI）—- 23
SCK （CLK）—— 18
VDD —————- 5V
VSS —————- GND
LEDA —————- 3V3
After programming, the screen can be lit up:
Although it can display, the effect is really poor, mainly because the contrast is too high, making it look very dark. This screen is actually quite useful, but adjusting the contrast is quite troublesome, and Mixly does not provide an adjustment program block. So what to do? We can only adjust it by modifying the parameters in the library function, first finding the location of this adjustment library function:
The file is located at…
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