34.7.5.9 Synchronization Busy

Table 34-34. Register Bit Attribute Legend
Symbol Description Symbol Description Symbol Description
R Readable bit HC Cleared by Hardware (Grey cell) Unimplemented
W Writable bit HS Set by Hardware X Bit is unknown at Reset
K Write to clear S Software settable bit — —
Name: SYNCBUSY
Offset: 0x1C
Reset: 0x00000000
Property: -

Bit 3130292827262524 
          
Access  
Reset  
Bit 2322212019181716 
          
Access  
Reset  
Bit 15141312111098 
          
Access  
Reset  
Bit 76543210 
    LENGTH CTRLBENABLESWRST 
Access RRRR 
Reset 0000 

Bit 4 – LENGTH LENGTH Synchronization Busy

Writing to the LENGTH register requires synchronization. When writing to LENGTH, SYNCBUSY.LENGTH will be asserted until synchronization is complete. If the LENGTH register is written to while SYNCBUSY.LENGTH is asserted, a bus error is generated.

Note: In client mode, the clock is only running during data transfer, so SYNCBUSY.LENGTH will remain asserted until the next data transfer begins.
ValueDescription
0 LENGTH synchronization is not busy.
1 LENGTH synchronization is busy.

Bit 2 – CTRLB CTRLB Synchronization Busy

Writing to the CTRLB when the SERCOM is enabled requires synchronization. Ongoing synchronization is indicated by SYNCBUSY.CTRLB=1 until synchronization is complete, after which the bit will read zero. If CTRLB is written while SYNCBUSY.CTRLB=1, a bus error will be generated.

ValueDescription
0 CTRLB synchronization is not busy.
1 CTRLB synchronization is busy.

Bit 1 – ENABLE SERCOM Enable Synchronization Busy

Enabling and disabling the SERCOM (CTRLA.ENABLE) requires synchronization. Ongoing synchronization is indicated by SYNCBUSY.ENABLE=1 until synchronization is complete, after which it will read zero.

ValueDescription
0 Enable synchronization is not busy.
1 Enable synchronization is busy.

Bit 0 – SWRST Software Reset Synchronization Busy

Resetting the SERCOM (CTRLA.SWRST) requires synchronization. Ongoing synchronization is indicated by SYNCBUSY.SWRST=1 until synchronization is complete, after which it will read zero.

ValueDescription
0 SWRST synchronization is not busy.
1 SWRST synchronization is busy.