AT32F425
Series Reference Manual
2022.03.30
Page 145
Ver 2.01
11.7.7 Status register (I2C_STS)
Bit
Register
Reset value
Type
Description
Bit 31: 24 Reserved
0x00
res
Kept at its default value.
Bit 23: 17 ADDR[6: 0]
0x00
r
Slave address matching value
In 7-bit address mode: Slave address received
In 10-bit address mode: 10-bit slave address header
received
Bit 16
SDIR
0x0
r
Slave data transfer direction
0: Receive data
1: Transmit data
Bit 15
BUSYF
0x0
r
Bus busy flag transmission mode
0: Bus idle
1: Bus busy
Once a START condition is detected, this bit is set;
Once a STOP condition is detected, this bit is automatically
cleared.
Bit 14
Reserved
0x00
res
Kept at its default value.
Bit 13
ALERTF
0x0
r
SMBus alert flag
SMBus host: This bit indicates the reception of an alert
signal (ALERT pin changes from high to low)
0: No alert signal received
1: Alert signal received
Bit 12
TMOUT
0x0
r
SMBus timeout flag
0: No timeout
1: Timeout
Bit 11
PECERR
0x0
r
PEC receive error flag
0: No PEC error
1: PEC error
Bit 10
OUF
0x0
r
Overrun or underrun flag
In transmission mode:
0: No overrun or underrun
1: Underrun
In reception mode:
0: No overrun or underrun
1: Overrun
Bit 9
ARLOST
0x0
r
Arbitration lost flag
0: No arbitration lost detected.
1: Arbitration lost detected.
Bit 8
BUSERR
0x0
rw0c
Bus error flag
0: No Bus error occurred
1: Bus error occurred
Bit 7
TCRLD
0x0
r
Data transfer complete, waiting for data load
0: Data transfer is not complete yet
1: Data transfer is complete
This bit is set when data transfer is complete (CNT=1) and
reload mode is enabled (RLDEN=1). It is automatically
cleared when writing a CNT value.
This bit is applicable in master mode or when SCTRL=1 in
slave mode.
Bit 6
TDC
0x0
r
Data transfer complete flag
0: Data transfer is not completed yet (the shift register still
holds data)
1: Data transfer is completed (shift register become empty
and all data has been sent to the bus)
This bit is set when ASTOPEN = 0
,
RLDEN = 0
,
CNT =
0.
It is automatically cleared after a START or a STOP
condition is received.
Bit 5
STOPF
0x0
r
Stop condition generation complete flag
0: No Stop condition detected.
1: Stop condition detected.
Bit 4
ACKFAILF
0x0
r
Acknowledge failure flag
0: No acknowledge failure