Extremely simplified LCD12864 display address conversion function

shipeng

Extremely simplified LCD12864 display address conversion function [Copy link]

 

Recently, acute obsessive-compulsive cancer has recurred. I decided to simplify the LCD12864 display address conversion function. The goal is not to see the branch structure in it. I racked my brains and spent countless time and finally barely completed it: Before simplification: //Set display position //x=0-7,y=0-3 void LCD_SetCursor(u8 x,u8 y) { if (y==0) {y=0x80;} else if (y==1) {y=0x90;} else if (y==2) {y=0x88;} else if (y==3) {y=0x98;} LCD_Wcmd(x+y); //Display address } After simplification: //Set display position //x=0-7,y=0-3 void LCD_SetCursor(u8 x,u8 y) { y=y>>1|y<<1&3; y=0x80+y*8; LCD_Wcmd(x+y); //Display address } I have always used it and the display is normal;

yulin3192

Newbies can't understand

shipeng

yulin3192 posted on 2018-4-15 19:30 Newbies can’t understand it

Have you ever used LCD12864?

star_66666

It's very simple, give it a thumbs up

一株草

Thanks for sharing

yulin3192

shipeng posted on 2018-4-16 09:31 Have you ever used LCD12864?

I am learning it now

yulin3192

shipeng posted on 2018-4-16 09:31 Have you ever used LCD12864?

I am currently learning

shipeng

yulin3192 posted on 2018-4-16 18:02 I am currently studying

This is actually the case: After analysis and summary, it was found that the value of y only needs to be swapped when it is 0b01 (1) or 0b10 (2), that is, 1 becomes 2, and 2 becomes 1. It remains unchanged when it is 0b00 (0) and 0b11 (3). After the conversion is completed, multiply the new y value by 8 and add 0x80.

yulin3192

shipeng posted on 2018-4-16 18:48 In fact, this is the situation: After analysis and summary, it is found that the value of y only needs to be interchanged when it is 0b01 (1) or 0b10 (2), that is, 1 becomes 2, and 2 becomes 1. 0b00 (0 ...

I still don't understand. Can the host send an example to see

shipeng

yulin3192 posted on 2018-4-16 20:23 I still don't understand. Can you please give me an example?

Let's take a look at the specification of LCD12864: The actual Y of the driver chip of LCD12864 is only 32 rows, and X is 16*16 columns. But the actual screen needs 64 rows and 8*16 columns. The implementation method is that when X is larger than 7*16 columns, it is used as Line3 and Line4, so the Y position of Line2 and Line3 needs to be swapped.

wjwjwjwj

Currently studying