0X4322: Spi Transmit Data Register (Spi_Txd) - Epson S1C17704 Technical Manual

19 SPI

0x4322: SPI Transmit Data Register (SPI_TXD)

Register name Address Bit
SPI Transmit 0x4322 D15–8 –
Data Register (16 bits)
D7–0 SPTDB[7:0] SPI transmit data buffer
(SPI_TXD)
D[15:8] Reserved
D[7:0] SPTDB[7:0]: SPI Transmit Data Buffer Bits
Set transmit data to be written to the transmit data buffer. (Default: 0x0)
In master mode, data transmission begins by writing data to this register. In slave mode, the register
contents are transferred to the shift register to start data transmission when a clock is input from the
master device.
SPTBE (D0/SPI_ST register) is set to 1 (empty) when the data is transferred to the shift register. At the
same time, a cause of transmit data buffer empty interrupt occurs. The next transmit data can be written
to the register at any time thereafter, even when the SPI is sending data.
The serial-converted data is output from the SDO pin beginning with the MSB, in which the bits set to
1 are output as high-level signals and those set to 0 output as low-level signals.
19-12
Name Function
reserved
SPTDB7 = MSB
SPTDB0 = LSB
EPSON
Setting Init. R/W
– – –
0x0 to 0xff 0x0 R/W
S1C17704 TECHNICAL MANUAL
Remarks
0 when being read.