Matrix Orbital LCD0821 Legacy User Manual
Page 18

LCD0821 rev 2
18
Custom characters occupy a 5 x 8 pixel matrix. Built-in characters are 5 x 7: the bottom row of pixels is
normally reserved for the underline cursor. The underline cursor should be turned off if the bottom row of
pixels forms part of a custom character.
The characters are defined by issuing the command 254 78 [c] followed by 8 bytes to define the character.
[c] is the character number (0x00 to 0x07). The 8 bytes are mapped as shown below:
MSB
LSB
* * * 1 2 3 4 5 Data
Byte
1
*
*
*
6
7
8
9
10 Data Byte 2
*
*
* 11 12 13
14 15 Data Byte 3
*
*
* 16 17 18
19 20 Data Byte 4
*
*
* 21 22 23
24 25 Data Byte 5
*
*
* 26 27 28
29 30 Data Byte 6
*
*
* 31 32 33
34 35 Data Byte 7
*
*
* 36 37 38
39 40 Data Byte 8
A "1" bit indicates an on (black) pixel, a "0" bit indicates an off (clear) pixel.
Once defined, a character is displayed simply by issuing a value (0x00 to 0x07) corresponding to the
character number. The character will be laid out as follows: