UPD78F1502AGK-GAK-AX Datasheet, PDF (716/1031 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcontrollers

78K0R/Lx3
CHAPTER 16 LCD CONTROLLER/DRIVER
16.7.5 Eight-time-slice display example
Figure 16-29 shows how the 15x8 dot LCD panel having the display pattern shown in Figure 16-28 is connected to the
segment signals (SEG4 to SEG18) and the common signals (COM0 to COM7). This example displays data "123" in the
LCD panel. The contents of the display data memory (addresses F0404H to F0412H) correspond to this display.
The following description focuses on numeral "3." ( ) displayed in the first digit. To display "3." in the LCD panel, it is
necessary to apply the select or deselect voltage to the SEG4 to SEG8 pins according to Table 16-8 at the timing of the
common signals COM0 to COM7; see Figure 16-28 for the relationship between the segment signals and LCD segments.
Table 16-9. Select and Deselect Voltages (COM0 to COM7)
Segment
Common
COM0
COM1
COM2
COM3
COM4
COM5
COM6
COM7
SEG4
Select
Deselect
Deselect
Deselect
Select
Select
Deselect
Deselect
SEG5
Select
Select
Deselect
Select
Deselect
Deselect
Select
Deselect
SEG6
Select
Deselect
Select
Deselect
Deselect
Deselect
Select
Deselect
SEG7
Select
Deselect
Deselect
Deselect
Deselect
Deselect
Select
Deselect
SEG8
Select
Deselect
Deselect
Deselect
Deselect
Select
Deselect
Deselect
According to Table 16-9, it is determined that the display data memory location (F0404H) that corresponds to SEG4
must contain 00110001.
Figure 16-30 shows examples of LCD drive waveforms between the SEG4 signal and each common signal. When the
select voltage is applied to SEG4 at the timing of COM0, a waveform is generated to turn on the corresponding LCD
segment.
Figure 18-28. Eight-Time-Slice LCD Display Pattern and Electrode Connections
SSSSS
EEEEE
GGGGG
n+4 n+3 n+2 n+1 n
COM0
COM1
COM2
COM3
COM4
COM5
COM6
COM7
Remark
78K0R/LF3: n = 4 to 26
78K0R/LG3: n = 4 to 35
78K0R/LH3: n = 4 to 49
R01UH0004EJ0501 Rev.5.01
700
Jun 20, 2011