Epson S1C17624 Technical Manual page 216

i C Master Data Register (i2CM_DaT)
2
Register name address Bit
i C Master Data 0x4344 D15–12 –
2
Register
(16 bits)
D11
(i2CM_DaT)
D10
D9
D8
D7–0 RTDT[7:0]
D[15:12] Reserved
D11 RBRDY: Receive Buffer Ready Flag Bit
Indicates the receive buffer status.
1 (R): Receive data exists
0 (R): No receive data (default)
The RBRDY flag becomes 1 when the data received in the shift register is loaded to RTDT[7:0] and
reverts to 0 when the receive data is read out from RTDT[7:0]. Interrupts can also be generated once the
flag value becomes 1.
note: Use the RBUSY flag when awaiting reception using polling in the S1C17602/621. The RBRDY
flag cannot be used to await reception with polling. For more information on awaiting reception
control procedures using polling, refer to "Data reception control" in Section 20.5.
In the S1C17624/604/622, the RBRDY flag can be used to await reception with polling. Ac-
cess the I2CM_DAT register in 16-bit size to read both RBRDY and RTDT[7:0] at a time and
use the RTDT[7:0] value as valid receive data when RBRDY = 1.
D10 RXe: Receive execution Bit
Receives 1 byte of data.
1 (R/W): Data reception start
0 (R/W): Ineffective (default)
Setting RXE to 1 and TXE to 0 starts receiving for 1 byte of data. RXE can be set to 1 for subsequent re-
ception, even if the slave address is being sent or data is being received. RXE is reset to 0 as soon as D7
is loaded to the shift register.
D9 TXe: Transmit execution Bit
Transmits 1 byte of data.
1 (R/W): Data transmission start
0 (R/W): Ineffective (default)
Transmission is started by setting the transmit data to RTDT[7:0] and writing 1 to TXE. TXE can be
set to 1 for subsequent transmission, even if the slave address or data is being sent. TXE is reset to 0 as
soon as the data set in RTDT[7:0] is transferred to the shift register.
D8 RTaCK: Receive/Transmit aCK Bit
When transmitting data
Indicates the response bit status.
1 (R/W): Error (NAK)
0 (R/W): ACK (default)
RTACK becomes 0 when ACK is returned from the slave after 1 byte of data is sent, indicating that the
slave has received the data correctly. If RTACK is 1, the slave device is not operating or the data was
not received correctly.
When receiving data
Sets the response bit sent to the slave.
1 (R/W): Error (NAK)
0 (R/W): ACK (default)
S1C17624/604/622/602/621 TeChniCal Manual
name Function
reserved
RBRDY
Receive buffer ready flag
RXe
Receive execution
TXe
Transmit execution
RTaCK Receive/transmit ACK
Receive/transmit data
RTDT7 = MSB
RTDT0 = LSB
Seiko epson Corporation
Setting init. R/W
–
1 Ready 0 Empty
1 Receive 0 Ignored
1 Transmit 0 Ignored
1 Error 0 ACK
0x0 to 0xff 0x0 R/W
2
20 i C MaSTeR (i2CM)
Remarks
– – 0 when being read.
0 R
0 R/W
0 R/W
0 R/W
20-9