41.8.18 Compare/Capture Channel x

The CCx register represents the 16-, 24- bit value, CCx. The register has two functions depending on the mode of operation.

For the capture operation, this register represents the second buffer level and access point for the CPU and DMA.

For the compare operation, this register is continuously compared to the counter value. Normally, the output from the comparator is, then, used for generating waveforms.

The CCx register is updated with the buffer value from their corresponding CCBUFx register when an UPDATE condition occurs.

In addition, in the match frequency operation, the CC0 register controls the counter period.

Name: CCx
Offset: 0x44 + x*0x04 [x=0..5]
Reset: 0x00000000
Property: Write-Synchronized, Read-Synchronized

Bit 3130292827262524 
          
Access  
Reset  
Bit 2322212019181716 
 CC[17:10] 
Access R/WR/WR/WR/WR/WR/WR/WR/W 
Reset 00000000 
Bit 15141312111098 
 CC[9:2] 
Access R/WR/WR/WR/WR/WR/WR/WR/W 
Reset 00000000 
Bit 76543210 
 CC[1:0]DITHER[5:0] 
Access R/WR/WR/WR/WR/WR/WR/WR/W 
Reset 00000000 

Bits 23:6 – CC[17:0] Channel x Compare/Capture Value

These bits hold the value of the Channel x compare/capture register.

Note:
  1. When the TCC is configured as a 16-bit timer/counter, the excess bits are read as zero.
  2. This bit field occupies the MSB of the register, [23:m]. m is dependent on the Resolution bit in the Control A register (CTRLA.RESOLUTION):
    CTRLA.RESOLUTIONBits [23:m]
    0x0 - NONE23:0
    0x1 - DITH423:4
    0x2 - DITH523:5
    0x3 - DITH623:6 (depicted)

Bits 5:0 – DITHER[5:0] Dithering Cycle Number

These bits hold the number of extra cycles that are added on the PWM pulse width every 64 PWM frames.
Note: This bit field consists of the n LSB of the register. n is dependent on the value of the Resolution bits in the Control A register (CTRLA.RESOLUTION):
CTRLA.RESOLUTIONBits [n:0]
0x0 - NONE-
0x1 - DITH43:0
0x2 - DITH54:0
0x3 - DITH65:0 (depicted)