Datasheet

Copyright © Parallax Inc. Parallax Serial LCDs (#27976, 27977, 27979) v3.1 3/11/2013 Page 7 of 11
Set Scale
The “set scale” commands (Dec 215 to 219) determines the octave each note will play in. This value
remains the same until another “set scale” command is received. The current octave can be set to a
value between 3 and 7, and each octave consists of 12 notes. The frequency for each note and scale
combination is shown in the table below.
Scale A A# B C C# D D# E F F# G G#
3 220 233 247 262 277 294 311 330 349 370 392 415
4 440 466 494 523 554 587 622 659 698 740 784 831
5 880 932 988 1047 1109 1175 1245 1319 1397 1480 1568 1661
6 1760 1865 1976 2093 2217 2349 2489 2637 2794 2960 3136 3322
7 3520 3729 3951 4186 4435 4699 4978 5274 5588 5920 6272 6645
Play Note
The “play note” commands (Dec 220 to 232) play a single note for the currently set time and in the
currently set octave.
Command Set
The tables on the following pages list all of the valid Serial LCD commands. Commands marked as N/A
are invalid and are ignored. The lines of the LCD display are numbered starting from 0, with line 0 being
the top line. The character positions on each line are numbered starting from 0, with position 0 being the
leftmost position on the line.
Dec Hex Action
0 00 Display custom character 0
1 01 Display custom character 1
2 02 Display custom character 2
3 03 Display custom character 3
4 04 Display custom character 4
5 05 Display custom character 5
6 06 Display custom character 6
7 07 Display custom character 7
8 08
Backspace / Left - The cursor is moved one position to the left. The
command doesn’t erase the character.
9 09
Right - The cursor is moved one position to the right. The
command doesn’t erase the character.
10 0A
Line Feed - The cursor is moved down one line. For the two line
LCD model, if on line 0 it goes to line 1. If on line 1, it wraps
around to line 0. The horizontal position remains the same.
Dec Hex Action
11 0B N/A
12 0C
Form Feed - The cursor is moved to position 0 on line 0 and the
entire display is cleared. Users must pause 5mS after this
command.
13 0D
Carriage Return – For the two line LCD model, if on line 0 the cursor
is moved to position 0 on line 1. If on line 1, it wraps around to
position 0 on line 0.
14 - 16 0E - 10 N/A
17 11 Turn backlight on (only on models 27977, 27979)