20 I
2
C
S1C17704 TECHNICAL MANUAL
EPSON
20-17
0x4344: I
2
C Data Register (I2C_DAT)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
I
2
C Data
Register
(I2C_DAT)
0x4344
(16 bits)
D15–12
–
reserved
–
–
–
0 when being read.
D11
RBRDY
Receive buffer ready
1 Ready
0 Empty
0
R
D10
RXE
Receive execution
1 Receive
0 Ignored
0
R/W
D9
TXE
Transmit execution
1 Transmit
0 Ignored
0
R/W
D8
RTACK
Receive/transmit ACK
1 Error
0 ACK
0
R/W
D7–0
RTDT[7:0]
Receive/transmit data
RTDT7 = MSB
RTDT0 = LSB
0x0 to 0xff
0x0
R/W
D[15:12] Reserved
D11
RBRDY: Receive Buffer Ready Flag
Indicates the receive buffer status.
1 (R):
Received data is present
0 (R):
No received data is present (default)
The RBRDY flag goes 1 when the received data in the shift register is loaded into RTDT[7:0] (D[7:0])
and returns to 0 when the received data is read from RTDT[7:0]. An interrupt can be generated when
this flag goes 1. Use this interrupt or read the RBRDY flag to check that RTDT[7:0] contains valid data
when reading received data.
D10
RXE: Receive Execution Bit
Execute a data reception for one byte.
1 (R/W): Start data reception
0 (R/W): Ignore (default)
The
I
2
C module starts data reception for one byte by setting RXE to 1 and TXE (D9) to 0. RXE can be
set to 1 for the next data reception even if a slave address is being transmitted or data is being received.
RXE is reset to 0 when D6 is input to the shift register.
D9
TXE: Transmit Execution Bit
Execute a data transmission for one byte.
1 (R/W): Start data transmission
0 (R/W): Ignore (default)
Set the transmit data to RTDT[7:0] (D[7:0]) and write 1 to TXE to start data transmission. TXE can be
set to 1 for the next data transmission even if a slave address or data is being transmitted. TXE is reset
to 0 when the data set in RTDT[7:0] is transferred to the shift register.
D8
RTACK: Receive/Transmit ACK Bit
In data transmission
Indicates the acknowledge bit status.
1 (R/W): Error (NACK)
0 (R/W): ACK (default)
This bit is set to 0 when the slave returned ACK after one-byte data has been transmitted. This indicates
that the slave could receive the data normally. If this bit is set to 1, the slave may be inactive or it could
not receive the data normally.
In data reception
Set the acknowledge bit to be sent to the slave.
1 (R/W): Error (NACK)
0 (R/W): ACK (default)
To return ACK to the slave after data is received, set RTACK to 0 before the I
2
C module sends the
acknowledge bit.
To return NACK, set RTACK to 1.
Summary of Contents for S1C17704
Page 1: ...TECHNICAL MANUAL S1C17704 CMOS 16 BIT SINGLE CHIP MICROCOMPUTER ...
Page 22: ...1 OVERVIEW 1 10 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 42: ...3 MEMORY MAP BUS CONTROL 3 12 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 82: ...6 INTERRUPT CONTROLLER ITC 6 26 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 108: ...8 CLOCK GENERATOR CLG 8 8 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 112: ...9 PRESCALER PSC 9 4 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 138: ...10 I O PORTS P 10 26 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 156: ...11 16 BIT TIMERS T16 11 18 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 208: ...14 8 BIT OSC1 TIMER T8OSC1 14 16 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 234: ...16 STOPWATCH TIMER SWT 16 14 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 242: ...17 WATCHDOG TIMER WDT 17 8 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 264: ...18 UART 18 22 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 300: ...20 I2C 20 20 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 320: ...21 REMOTE CONTROLLER REMC 21 20 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 360: ...24 ON CHIP DEBUGGER DBG 24 6 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 362: ...25 BASIC EXTERNAL WIRING DIAGRAM 25 2 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...