User manual

...the world's most energy friendly microcontrollers
2012-04-24 - Giant Gecko Family - d0053_Rev0.96 792
www.energymicro.com
Figure 33.43. LCD Clock System in LCD Driver
LFXO
LFRCO
Counter
FDIV[2:0]
LCD Frame
Counter
FCTOP[5:0]
LFACLK
LCDpre
CLK
FC
CLK
EVENT
div2
CLK
FRAME
MUX in
LCD_DISPCTRL
LFACLK
LCD
LCD in
CMU_LFAPRESC0
CMU
div16
div32
div64
div128
div1
div2
div4
div8
FCPRESC in
LCD_BACTRL
LFACLK
div4
div6
div8
div12
div16
static
duplex
triplex
quadruplex
sextaplex
octaplex
33.3.11 LCD Interrupt
The LCD interrupt can be used to synchronize data update. The FC interrupt flag is set at every LCD
Frame Counter Event, which must be set-up separately. The interrupt is enabled by setting FC bit in
LCD_IEN.
33.3.12 Blink, Blank, and Animation Features
33.3.12.1 Blink
The LCD driver can be configured to blink, alternating all enabled segments between on and off. The blink
frequency is given by the CLK
EVENT
frequency, see Section 33.3.10 (p. 791) . See Section 33.3.8 (p.
790) for details regarding synchronization of the blink feature. The FC must be on for blink to work.
33.3.12.2 Blank
Setting BLANK in LCD_BACTRL will output the “OFF” waveform on all enabled segments, effectively
blanking the entire display. Writing the BLANK bit to zero disables the blanking and segment data will
be output as normal. See Section 33.3.8 (p. 790) for details regarding synchronization of blank.
33.3.12.3 Animation State Machine
The Animation State Machine makes it possible to enable different animations without updating the data
registers, allowing specialized patterns running on the LCD panel while the microcontroller remains in
Low Energy Mode and thus saving power consumption. The animation feature is available on 8 segments
multiplexed with LCD_COM0. The 8 segments can be either segments 0 to 7 or 8 to 15, depending on
ALOC in LCD_BACTRL. The animation is implemented as two programmable 8 bits registers that are
shifted left or right every other Animation state for a total of 16 states.
The shift operations applied to the shift registers are controlled by AREGASC and AREGBSC in
LCD_BACTRL as shown in the table below. Note also that the FC must be on for animation to work, as
it is the FC event that drives the animation state machine.