Datasheet

36.10.1 Control A
Name: CTRLA
Offset: 0x00
Reset: 0x00000000
Property: PAC Write-Protection, Enable-Protected, Write-Synchronized
Bit 31 30 29 28 27 26 25 24
LOWTOUT INACTOUT[1:0] SCLSM SPEED[1:0]
Access
R/W R/W R/W R/W R/W R/W
Reset 0 0 0 0 0 0
Bit 23 22 21 20 19 18 17 16
SEXTTOEN MEXTTOEN SDAHOLD[1:0] PINOUT
Access
R/W R/W R/W R/W R/W
Reset 0 0 0 0 0
Bit 15 14 13 12 11 10 9 8
Access
Reset
Bit 7 6 5 4 3 2 1 0
RUNSTDBY MODE[2:0] ENABLE SWRST
Access
R/W R/W R/W R/W R/W R/W
Reset 0 0 0 0 0 0
Bit 30 – LOWTOUT SCL Low Time-Out
This bit enables the SCL low time-out. If SCL is held low for 25ms-35ms, the master will release its clock
hold, if enabled, and complete the current transaction. A stop condition will automatically be transmitted.
INTFLAG.SB or INTFLAG.MB will be set as normal, but the clock hold will be released. The
STATUS.LOWTOUT and STATUS.BUSERR status bits will be set.
This bit is not synchronized.
Value Description
0
Time-out disabled.
1
Time-out enabled.
Bits 29:28 – INACTOUT[1:0] Inactive Time-Out
If the inactive bus time-out is enabled and the bus is inactive for longer than the time-out setting, the bus
state logic will be set to idle. An inactive bus arise when either an I
2
C master or slave is holding the SCL
low.
Enabling this option is necessary for SMBus compatibility, but can also be used in a non-SMBus set-up.
Calculated time-out periods are based on a 100kHz baud rate.
These bits are not synchronized.
Value Name Description
0x0
DIS Disabled
0x1
55US 5-6 SCL cycle time-out (50-60µs)
0x2
105US 10-11 SCL cycle time-out (100-110µs)
SAM D5x/E5x Family Data Sheet
SERCOM I2C – Inter-Integrated Circuit
© 2019 Microchip Technology Inc.
Datasheet
DS60001507E-page 1049