AT32F421
Series Reference Manual
2022.11.11
Page 128
Rev 2.02
received.
When STRETCH=0
In reception mode, when a new byte (including ACK
pulse) is received and the data register is not read yet
(RDBF=1)
In transmission mode, when a new byte is sent and the
data register is not written yet (TDBE=1)
The TDC is set under both conditions.
Bit 1
ADDR7F
0x0
ro
0~7 bit address match flag
0: Address is not sent in host ode or received in slave
mode
1: Address is sent in host mode or address is received in
slave mode.
Cleared by read access to STS2 register after the
software reads STS1 register.
Note: the ADDR7F bit is not set after a NACK reception.
Bit 0
STARTF
0x0
ro
Start condition generation complete flag
0: No Start condition is generated.
1: Start condition is generated.
Cleared by write access to the DT register after the
software reads the STS1 register.
11.5.7 Status register2 (I2C_STS2)
Bit
Register
Reset value
Type
Description
Bit 15: 8
PECVAL
0x00
ro
PEC value
Cleared when PECEN is reset.
Bit 7
ADDR2F
0x0
ro
Received address 2 flag
0: Received address matches the contents of OADDR1
1: Received address matches the contents of OADDR2
Cleared when a Stop/Start condition is received, or by
hardware when I2CEN=0.
Bit 6
HOSTADDRF
0x0
ro
SMBus host address reception flag
0: SMBus host address is not received.
1: SMBus host address is received.
Cleared when a Stop/Start condition is received, or by
hardware when I2CEN=0.
Bit 5
DEVADDRF
0x0
ro
SMBus device address reception flag
0: SMBus device address is not received.
1: SMBus device address is received.
Cleared when a Stop/Start condition is received, or by
hardware when I2CEN=0.
Bit 4
GCADDRF
0x0
ro
General call address reception flag
0: General call address is not received.
1: General call address is received.
Cleared when a Stop/Start condition is received, or by
hardware when I2CEN=0.
Bit 3
Reserved
0x0
resd
Keep at its default value.
Bit 2
DIRF
0x0
ro
Transmission direction flag
0: Data reception
1: Data transmission
Cleared by hardware when a Stop condition is received.
Bit 1
BUSYF
0x0
ro
Bus busy flag transmission mode
0: Bus idle
1: Bus busy
Set by hardware on detection of SDA/SCL low, and