19 UNIVERSAL SERIAL INTERFACE WITH LCD INTERFACE (USIL)
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
19-33
8.2 Interface Mode Selection
Table 19.
USILMOD[2:0]
Interface mode
0x7
LCD parallel
0x6
LCD SPI
0x5
I
2
C slave
0x4
I
2
C master
0x3
SPI slave
0x2
SPI master
0x1
UART
0x0
Software reset
(Default: 0x0)
Perform software reset (set USILMOD[2:0] to 0x0) and then set the interface mode before changing
other USIL configurations.
USIL Transmit Data Buffer Register (USIL_TD)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
USIL
Transmit Data
Buffer Register
(USIL_TD)
0x300601
(8 bits)
D7–0 TD[7:0]
USIL transmit data buffer
TD7 = MSB
TD0 = LSB
0x0 to 0xff
0x0 R/W
D[7:0]
TD[7:0]: USIL Transmit Data Buffer Bits
Sets transmit data to be written to the transmit data buffer. (Default: 0x0)
In UART, SPI master, LCD SPI, and LCD parallel modes, transmission begins immediately after writ-
ing data to this register. In SPI slave mode, transmission will begin when the clock is input from the SPI
master device.
In I
2
C master/slave mode, transmission begins by the software trigger for data transmission.
The data written to this register is converted into serial data through the shift register and is output from
the USIL_DO pin with the bit set to 1 as high level and the bit set to 0 as low level.
In LCD parallel mode, the data written to this register is output via the LCD_D[7:0] pins.
A transmit (write) buffer empty interrupt can be generated when data written to this register has been
transferred to the shift register or output from the LCD_D[7:0] pins. The subsequent transmit data can
then be written, even while data is being sent.
USIL Receive Data Buffer Register (USIL_RD)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
USIL Receive
Data Buffer
Register
(USIL_RD)
0x300602
(8 bits)
D7–0 RD[7:0]
USIL receive data buffer
RD7 = MSB
RD0 = LSB
0x0 to 0xff
0x0
R
D[7:0]
RD[7:0]: USIL Receive Data Buffer Bits
Contains the received data. (Default: 0x0)
Serial data input from the USIL_DI pin is converted to parallel, with the high level bit set to 1 and the
low level bit set to 0, and then it is loaded to this register. In LCD parallel mode, data input from the
LCD_D[7:0] pins are loaded to this register.
A receive (read) buffer full interrupt can be generated when the data received has been loaded to this
register. Data can then be read until subsequent data is received.
This register is read-only.
USIL UART Mode Configuration Register (USIL_UCFG)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
USIL
UART Mode
Configuration
Register
(USIL_UCFG)
0x300640
(8 bits)
D7–4 –
reserved
–
–
–
0 when being read.
D3
UCHLN
Character length select
1 8 bits
0 7 bits
0
R/W
D2
USTPB
Stop bit select
1 2 bits
0 1 bit
0
R/W
D1
UPMD
Parity mode select
1 Even
0 Odd
0
R/W
D0
UPREN
Parity enable
1 With parity
0 No parity
0
R/W