Atmel Xplained Pro Evaluation Kit ATSAMD20-XPRO ATSAMD20-XPRO Data Sheet
Product codes
ATSAMD20-XPRO
429
Atmel | SMART SAM D20 [DATASHEET]
Atmel-42129K–SAM-D20_datasheet–06/2014
26.8.2.7 Interrupt Flag Status and Clear
Name:
INTFLAG
Offset:
0x0E
Reset:
0x00
Property:
-
z
Bits 7:2 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always write these bits to
zero when this register is written. These bits will always return zero when read.
These bits are unused and reserved for future use. For compatibility with future devices, always write these bits to
zero when this register is written. These bits will always return zero when read.
z
Bit 1 – SB: Slave on Bus
The Slave on Bus flag (SB) is set when a byte is successfully received in master read mode, i.e., no arbitration lost
or bus error occurred during the operation. When this flag is set, the master forces the SCL line low, stretching the
I
The Slave on Bus flag (SB) is set when a byte is successfully received in master read mode, i.e., no arbitration lost
or bus error occurred during the operation. When this flag is set, the master forces the SCL line low, stretching the
I
2
C clock period. The SCL line will be released and SB will be cleared on one of the following actions:
z
Writing to ADDR.ADDR
z
Writing to DATA.DATA
z
Reading DATA.DATA when smart mode is enabled (CTRLB.SMEN)
z
Writing a valid command to CTRLB.CMD
Writing a one to this bit location will clear the SB flag. The transaction will not continue or be terminated until one of
the above actions is performed.
the above actions is performed.
Writing a zero to this bit has no effect.
z
Bit 0 – MB: Master on Bus
The Master on Bus flag (MB) is set when a byte is transmitted in master write mode. The flag is set regardless of
the occurrence of a bus error or an arbitration lost condition. MB is also set when arbitration is lost during sending
of NACK in master read mode, and when issuing a start condition if the bus state is unknown. When this flag is set
and arbitration is not lost, the master forces the SCL line low, stretching the I
The Master on Bus flag (MB) is set when a byte is transmitted in master write mode. The flag is set regardless of
the occurrence of a bus error or an arbitration lost condition. MB is also set when arbitration is lost during sending
of NACK in master read mode, and when issuing a start condition if the bus state is unknown. When this flag is set
and arbitration is not lost, the master forces the SCL line low, stretching the I
2
C clock period. The SCL line will be
released and MB will be cleared on one of the following actions:
z
Writing to ADDR.ADDR
z
Writing to DATA.DATA
z
Reading DATA.DATA when smart mode is enabled (CTRLB.SMEN)
z
Writing a valid command to CTRLB.CMD
If arbitration is lost, writing a one to this bit location will clear the MB flag.
If arbitration is not lost, writing a one to this bit location will clear the MB flag. The transaction will not continue or be
terminated until one of the above actions is performed.
terminated until one of the above actions is performed.
Writing a zero to this bit has no effect.
Bit
7
6
5
4
3
2
1
0
SB
MB
Access
R
R
R
R
R
R
R/W
R/W
Reset
0
0
0
0
0
0
0
0