19 UNIVERSAL SERIAL INTERFACE WITH LCD INTERFACE (USIL)
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
19-7
Slave mode
USIL_CK (SCPOL = 1, SCPHA = 1)
USIL_CK (SCPOL = 1, SCPHA = 0)
USIL_CK (SCPOL = 0, SCPHA = 1)
USIL_CK (SCPOL = 0, SCPHA = 0)
USIL_DI
USIL_DO
Fetching received data
into shift register
D7 (MSB)
D0 (LSB)
D7 (MSB)
D0
4.5.1 Clock and Data Transfer Timing (MSB first)
Figure 19.
Clock mode (master mode only)
In SPI master mode, either normal or fast clock mode can be selected using SFSTMOD/USIL_SCFG register.
Setting SFSTMOD to 0 (default) places the USIL into normal mode and the USIL generates the transfer clock
by dividing the T8 output by 2. Setting SFSTMOD to 1 places the USIL into fast mode and the USIL uses
PCLK2 supplied from the CMU directly as the transfer clock. The fast mode does not use the T8.
The SPI slave mode uses the T8 output clock for generating the sampling clock.
Settings for I
19.4.6
2
C Mode
The I
2
C mode does not need to set data format and other conditions. The data length in I
2
C mode is fixed at 8 bits.
Settings for LCD SPI Mode
19.4.7
When the USIL is used in LCD SPI mode, configure the SPI clock polarity/phase and the data format.
SPI clock polarity and phase settings
Use LSCPOL/USIL_LSCFG register to select the SPI clock polarity. Setting LSCPOL to 1 treats the SPI clock
as active low. Setting it to 0 (default) treats it as active high.
The SPI clock phase can be selected using LSCPHA/USIL_LSCFG register.
These control bits set transfer timing as shown in Figure 19.4.7.1.
USIL_CK (LSCPOL = 1, LSCPHA = 1)
USIL_CK (LSCPOL = 1, LSCPHA = 0)
USIL_CK (LSCPOL = 0, LSCPHA = 1)
USIL_CK (LSCPOL = 0, LSCPHA = 0)
USIL_DO
Slave device data fetch timing
CMD
D7 (MSB)
D0 (LSB)
4.7.1 Clock and Data Transfer Timing (Command bit enabled, MSB first)
Figure 19.
Data format
In LCD SPI mode, the display data format can be selected using LSDMOD[1:0]/USIL_LSDCFG register.
4.7.1 LCD SPI Data Mode
Table 19.
LSDMOD[1:0]
Data mode
0x3
24-bit mode
0x2
18-bit mode
0x1
16-bit mode
0x0
8-bit mode
(Default: 0x0)