2 lcd controller operation, 1 lcd memory, 2 blinking the lcd – Texas Instruments MSP430x4xx User Manual

Page 335: 3 lcd timing generation

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LCD Controller Operation

18-4

LCD Controller

18.2 LCD Controller Operation

The LCD controller is configured with user software. The setup and operation
of LCD controller is discussed in the following sections.

18.2.1 LCD Memory

The LCD memory map is shown in Figure 18−2. Each memory bit corresponds
to one LCD segment, or is not used, depending on the mode. To turn on an
LCD segment, its corresponding memory bit is set.

Figure 18−2. LCD memory

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3

2

1

0

3

2

1

0

Associated

Common Pins

097h

Address

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098h

099h

09Ah

09Bh

09Ch

09Dh

09Eh

09Fh

0A0h

0A1h

0A2h

0A3h

0A4h

29, 28
27, 26

25, 24
23, 22
21, 20

19, 18
17, 16

15, 14
13, 12

11, 10

9, 8
7, 6
5, 4

3, 2

1, 0

7

0

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Associated

Segment Pins

Sn+1

Sn

28
26

24
22
20

18
16

14
12
10

8
6
4

2

0

n

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092h

093h

094h

095h

096h

31, 30

33, 32

35, 34

37, 36

39, 38

30

32

34

36

38

091h

18.2.2 Blinking the LCD

The LCD controller supports blinking. The LCDSON bit is ANDed with each
segment’s memory bit. When LCDSON = 1, each segment is on or off
according to its bit value. When LCDSON = 0, each LCD segment is off.

18.2.3 LCD Timing Generation

The LCD controller uses the f

LCD

signal from the Basic Timer1 to generate the

timing for common and segment lines. The proper frequency f

LCD

depends on

the LCD’s requirement for framing frequency and LCD multiplex rate. See the
Basic Timer1 chapter for more information on configuring the f

LCD

frequency.

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