upd70f3422gj-gae-qs-ax Renesas Electronics Corporation., upd70f3422gj-gae-qs-ax Datasheet - Page 818

• Manufacturer Part Number: upd70f3422gj-gae-qs-ax
• Description: 32-bit Single-chip Microcontroller
• Manufacturer: Renesas Electronics Corporation.

Chapter 22
818
Figure 22-6
Table 22-8
22.3.2 Activation of LCD segments
22.4 Display Example
(1)
An LCD segment becomes visible when the potential difference of the
corresponding common signal and segment signal reaches or exceeds the
LCD drive voltage V
their selection levels.
Within one frame cycle T
Activation lasts for one duty cycle T. LCD segments corresponding to common
signals COM0 to COM3 are not activated simultaneously, but consecutively.
As a display example, register contents and output signals for a 20-digit LCD
display are presented in this section.
LCD panel
The display pattern of a single digit is given below. Each digit is addressed by
two segment signals and four common signals.
4-time-division LCD pattern and electrode connections
Figure 22-7 on page 820 shows the whole LCD panel and its connection to the
segment signals and common signals. The display example is
“123456.78901234567890,” and the register contents of SEGREG0k (k = 0 to
39) correspond to this.
An explanation is given here taking the example of the 6th digit with point: “6.”.
The corresponding segment signals are output to pins SEG28 and SEG29 with
the selection levels at the COM0 to COM3 common signal timings as shown in
the table below:
Selection and non-selection levels of example
Preliminary User’s Manual U17566EE1V2UM00
Common signal
COM0
COM1
COM2
COM3
SEG
SEG
2n + 1
2n
LCD
. This is achieved if common and segment signal are at
F
, each LCD segment can be activated once.
selected
selected
selected
Segment signal SEG28
not selected
COM2
COM0
LCD Controller/Driver (LCD-C/D)
Segment signal SEG29
selected
selected
selected
selected
COM1
COM3