Atmel Xplained Pro Evaluation Kit for the ATSAMD21J18A Microcontroller ATSAMD21-XPRO ATSAMD21-XPRO Data Sheet

Product codes
ATSAMD21-XPRO
Page of 1018
552
Atmel | SMART SAM D21 [DATASHEET]
Atmel-42181C–SAM-D21_Datasheet–07/2014
27.8.2.7  Status
Name:
STATUS
Offset:
0x1A
Reset:
0x0000
Property:
Write-Synchronized
z
Bits 15:11 – 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.
z
Bit 10 – LENERR: Transaction Length Error
This bit is set when automatic length is used for a DMA transaction and the slave sends a NACK before 
ADDR.LEN bytes have been written by the master. 
Writing a one to this bit location will clear STATUS.LENERR. This flag is automatically cleared when writing to the 
ADDR register.
Writing a zero to this bit has no effect. 
This bit is not write-synchronized.
z
Bit 9 – SEXTTOUT: Slave SCL Low Extend Time-Out
This bit is set if a slave SCL low extend time-out occurs. 
Writing a one to this bit location will clear STATUS.SEXTTOUT. Normal use of the I
2
C interface does not require 
the STATUS.SEXTTOUT flag to be cleared by this method. This flag is automatically cleared when writing to the 
ADDR register.
Writing a zero to this bit has no effect. 
This bit is not write-synchronized.
z
Bit 8 – MEXTTOUT: Master SCL Low Extend Time-Out
This bit is set if a master SCL low time-out occurs. 
Writing a one to this bit location will clear STATUS.MEXTTOUT. Normal use of the I
2
C interface does not require 
the STATUS.MEXTTOUT flag to be cleared by this method. This flag is automatically cleared when writing to the 
ADDR register.
Writing a zero to this bit has no effect. 
This bit is not write-synchronized.
z
Bit 7 – CLKHOLD: Clock Hold
The Master Clock Hold flag (STATUS.CLKHOLD) is set when the master is holding the SCL line low, stretching 
the I
2
C clock. Software should consider this bit a read-only status flag that is set when INTFLAG.SB or INT-
Bit
15
14
13
12
11
10
9
8
LENERR
SEXTTOUT
MEXTTOUT
Access
R
R
R
R
R
R/W
R/W
R/W
Reset
0
0
0
0
0
0
0
0
Bit
7
6
5
4
3
2
1
0
CLKHOLD
LOWTOUT
BUSSTATE[1:0]
RXNACK
ARBLOST
BUSERR
Access
R
R/W
R
R/W
R
R
R/W
R/W
Reset
0
0
0
0
0
0
0
0