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RM0365
Inter-integrated circuit (I2C) interface
834
28.7.7
Interrupt and status register (I2C_ISR)
Address offset: 0x18
Reset value: 0x0000 0001
Access: No wait states
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
ADDCODE[6:0]
DIR
r
r
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
BUSY
Res.
ALERT
TIME
OUT
PEC
ERR
OVR
ARLO
BERR
TCR
TC
STOPF NACKF ADDR
RXNE
TXIS
TXE
r
r
r
r
r
r
r
r
r
r
r
r
r
rs
rs
Bits 31:24 Reserved, must be kept at reset value.
Bits 23:17
ADDCODE[6:0]
: Address match code (Slave mode)
These bits are updated with the received address when an address match event occurs
(ADDR = 1).
In the case of a 10-bit address, ADDCODE provides the 10-bit header followed by the 2 MSBs
of the address.
Bit 16
DIR
:
Transfer direction (Slave mode)
This flag is updated when an address match event occurs (ADDR=1).
0: Write transfer, slave enters receiver mode.
1: Read transfer, slave enters transmitter mode.
Bit 15
BUSY
:
Bus busy
This flag indicates that a communication is in progress on the bus. It is set by hardware when a
START condition is detected. It is cleared by hardware when a Stop condition is detected, or
when PE=0.
Bit 14 Reserved, must be kept at reset value.
Bit 13
ALERT
: SMBus alert
This flag is set by hardware when SMBHEN=1 (SMBus host configuration), ALERTEN=1 and
a SMBALERT event (falling edge) is detected on SMBA pin. It is cleared by software by setting
the ALERTCF bit.
Note: This bit is cleared by hardware when PE=0.
If the SMBus feature is not supported, this bit is reserved and forced by hardware to ‘0’.
Please refer to
Section 28.3: I2C implementation
Bit 12
TIMEOUT
: Timeout or t
LOW
detection flag
This flag is set by hardware when a timeout or extended clock timeout occurred. It is cleared
by software by setting the TIMEOUTCF bit.
Note: This bit is cleared by hardware when PE=0.
If the SMBus feature is not supported, this bit is reserved and forced by hardware to ‘0’.
Please refer to