mc68hc05l25 Freescale Semiconductor, Inc, mc68hc05l25 Datasheet - Page 101

• Manufacturer Part Number: mc68hc05l25
• Description: M68hc05 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

11.3.2 Fast Change Option
The R
applications. For those applications that require less DC current drain through the R
increased to approximately 860 kΩ at V
require the default resistance to drive the capacitive load of the LCD panel, yet do not wish to have the
DC current drain of it while the LCD segments are not switching. For a compromise, a fast-charge option
is available. The R
before the LCD segments change, and then are set to low-current mode for the remainder of the LCD
cycle frame. The DC current increase is very negligible and will be within a few percent increase of the
low-current mode.
11.3.3 LCD Data Registers
The LCD data latches LDAT1 through LDAT11 maintain the ON/OFF data for the FP and BP segments
of the LCD.
Four bits of data latch are assigned to each frontplane driver from address space $21 through $2D as
shown in
When a logic 1 is written to the bits in the data latch, the applicable FP-BP segment turns ON. When a
logic 0 is written to the bits, the segment is turned OFF.
The values in the data latches are not initialized and are unknown on reset.
If 1/3 duty is selected, each BP3 bit in the data latches is ignored.
Freescale Semiconductor
LCD
Figure
is approximately 160 kΩ at V
FC
X
0
1
11-4.
LCD
LC
0
1
1
values are reduced to the default resistance for a fraction of the LCD segment cycle
BP0
FC CLOCK
Default value of approximately 160 kΩ per resistor
Resistor value of approximately 860 kΩ per resistor
Fast-Charge: For a period of LCDCLK/128 in each frame, the resistor values
are reduced to default (value for LC = 0).
Figure 11-3. BP0/FC Clock Timing
Table 11-1. R
MC68HC05L25 Data Sheet, Rev. 3.1
DD
DD
= 3 V by default. This value can be inappropriate for some
= 3 V by setting the LC bit in LCDCR. Some applications may
LCD
Configuration
Action
LCD
Functional Description
chain, it may be
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