26 LCD CONTROLLER (LCDC)
26-34
Seiko Epson Corporation
S1C33L26 TECHNICAL MANUAL
6. Sub-window start position
PIP_XSTART[9:0] = 80 pixels
×
4 bpp
÷
32 bits = 10 words = 0x0a
PIP_YSTART[9:0] = 60 lines = 0x3c
LCDC_SUBSP register = 0x803c000a
The MSB in this register is the sub-window enable bit. Setting the MSB enables the sub-window to be dis-
played.
7. Note on using 12 bpp or 24 bpp mode
If the LCDC is used in 12 bpp or 24 bpp mode, the addresses must be aligned with a 3-word boundary.
LCDC_MAINADR register = 0x10 3n (words)
LCDC_SUBADR register = 0x10 3n (words)
PIP_XSTART[9:0] = 3n (words)
PIP_XEND[9:0] = 3n + 2 (words)
LCDC Interrupt
26.7
The LCDC module can generate frame interrupts.
Frame interrupt
To use this interrupt, set FRINTEN/LCDC_INT register to 1. If FRINTEN is set to 0 (default), interrupt re-
quests for this cause will not be sent to the ITC.
When a vertical non-display period begins after a frame refresh cycle (vertical display period) has finished,
VNDPF/LCDC_PSAVE register is set to 1. At the same time, FRINTF/LCDC_PSAVE register is set to 1 and the
LCDC outputs an interrupt signal to the interrupt controller (ITC) if frame interrupts are enabled (FRINTEN = 1).
An interrupt occurs if other interrupt conditions are met.
FPFRAME
FPLINE
FRINTF
VNDPF
VDP
VNDP (e.g. 3 lines)
Interrupt is generated
Reset by writing 1
7.1 Frame Interrupt Timing
Figure 26.
For more information on interrupt processing, see the “Interrupt Controller (ITC)” chapter.
Power Save
26.8
The LCD controller has a power-save modes. Use PSAVE[1:0]/LCDC_PSAVE register to set the power-save mode.
8.1 Power-Save Mode Settings
Table 26.
PSAVE[1:0]
Mode
0x3
Normal operation
0x2
Reserved
0x1
Reserved
0x0
Power-save mode
(Default: 0x0)
Power-save mode
When the LCD controller enters this mode, all LCD signal output pins are dropped low, with the LCD panel
placed in power-down mode. All operations of the LCD controller, other than accessing of its control registers
and look-up tables are disabled.
The LCD controller is placed in power-save mode by setting PSAVE[1:0] to 0x0.
The LCD controller is taken out of power-save mode by setting PSAVE[1:0] to 0x3.