44.7.1 Comparator Control A

Table 44-2. Register Bit Attribute Legend
SymbolDescriptionSymbolDescriptionSymbolDescription
RReadable bitHCCleared by Hardware(Grey cell)Unimplemented
WWritable bitHSSet by HardwareXBit is unknown at Reset
KWrite to clearSSoftware settable bit
Name: CTRLA
Offset: 0x00
Reset: 0x00000000
Property: PAC Write-Protection, Write-Synchronized

Bit 3130292827262524 
          
Access  
Reset  
Bit 2322212019181716 
          
Access  
Reset  
Bit 15141312111098 
          
Access  
Reset  
Bit 76543210 
       ENABLESWRST 
Access R/WW 
Reset 00 

Bit 1 – ENABLE Enable

Due to synchronization, there is delay from updating the register until the peripheral is enabled/disabled. The value written to CTRL.ENABLE will read back immediately and the corresponding bit in the Synchronization Busy register (SYNCBUSY.ENABLE) will be set. SYNCBUSY.ENABLE is cleared when the peripheral is enabled/disabled.

ValueDescription
0The AC is disabled.
1The AC is enabled. Each comparator must also be enabled individually by the Enable bit in the Comparator Control register (COMPCTRLn.ENABLE).

Bit 0 – SWRST Software Reset 1. When the CTRLA.SWRST is written, the user should poll the SYNCB.SWRST bit to know when the reset operation is complete. 2. During a SWRST, access to registers/bits without SWRST are disallowed until SYNCBUSY.SWRST is cleared by hardware.

Writing a '0' to this bit has no effect.

Writing a '1' to this bit resets all registers in the AC to their initial state, and the AC will be disabled.

Writing a '1' to CTRLA.SWRST will always take precedence, meaning that all other writes in the same write-operation will be discarded.

Due to synchronization, there is a delay from writing CTRLA.SWRST until the reset is complete. CTRLA.SWRST and SYNCBUSY.SWRST will both be cleared when the reset is complete.

Note: To avoid spurious interrupts from enable/disable cycles, use the SWRST bit to reset the comparator module.
ValueDescription
0There is no reset operation ongoing.
1The reset operation is ongoing.