34.7.3 Control B Set
| Name: | CTRLBSET |
| Offset: | 0x05 |
| Reset: | 0x00 |
| Property: | PAC Write-Protection, Write-Synchronized, Read-Synchronized |
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| CMD[2:0] | IDXCMD[1:0] | ONESHOT | LUPD | DIR | |||||
| Access | R/W | R/W | R/W | R/W | R/W | R/W | R/W | R/W | |
| Reset | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
Bits 7:5 – CMD[2:0] TCC Command
These bits can be used for software control of re-triggering and stop commands of the TCC. When a command has been executed, the CMD bit field will be read back as zero. The commands are executed on the next prescaled GCLK_TCC clock cycle.
Writing zero to this bit group has no effect
Writing a value different from 0x0 to this bit field will issue a command for execution.
- Issue CMD command (CTRLBSET.CMD = command)
- Wait for CMD synchronization (SYNCBUSY.CTRLB = 0)
- Wait for CMD read back as zero (CTRLBSET.CMD = 0)
| Value | Name | Description |
|---|---|---|
| 0x0 | NONE | No action |
| 0x1 | RETRIGGER | Force start, restart or retrigger |
| 0x2 | STOP | Force stop |
| 0x3 | UPDATE | Force update of double buffered registers |
| 0x4 | READSYNC | Force a read synchronization of COUNT |
| 0x5 | DMAOS | One-shot DMA trigger |
Bits 4:3 – IDXCMD[1:0] Ramp Index Command
These bits can be used to force cycle A and cycle B changes in RAMP2 and RAMP2A operation. On timer/counter update condition, the command is executed, the IDX flag in STATUS register is updated and the IDXCMD command is cleared.
Writing a zero to these bits has no effect.
Writing a valid value to these bits will set a command.
| Value | Name | Description |
|---|---|---|
| 0x0 | DISABLE | Command disabled: IDX toggles between cycles A and B |
| 0x1 | SET | Set IDX: cycle B will be forced in the next cycle |
| 0x2 | CLEAR | Clear IDX: cycle A will be forced in next cycle |
| 0x3 | HOLD | Hold IDX: the next cycle will be the same as the current cycle. |
Bit 2 – ONESHOT One-Shot
This bit controls one-shot operation of the TCC. When in one-shot operation, the TCC will stop counting on the next overflow/underflow condition or a stop command.
Writing a '0' to this bit has no effect.
Writing a '1' to this bit will enable the one-shot operation.
| Value | Description |
|---|---|
| 0 | The TCC will count continuously. |
| 1 | The TCC will stop counting on the next underflow/overflow condition. |
Bit 1 – LUPD Lock Update
This bit controls the update operation of the TCC buffered registers.
When CTRLB.LUPD is set, the hardware UPDATE registers with value from their buffered registers is disabled. Disabling the update ensures that all buffer registers are valid before a hardware update is performed. After all the buffer registers are loaded correctly, the buffered registers can be unlocked.
This bit has no effect when input capture operation is enabled.
Writing a '0' to this bit has no effect.
Writing a '1' to this bit will disable the registers updates on hardware UPDATE condition.
| Value | Description |
|---|---|
| 0 | The CCBx, PERB, PGVB, PGOB, and SWAPBx buffer registers values are copied into the corresponding CCx, PER, PGV, PGO and SWAPx registers on hardware update condition. |
| 1 | The CCBx, PERB, PGVB, PGOB, and SWAPBx buffer registers values are not copied into CCx, PER, PGV, PGO and SWAPx registers on hardware update condition. |
Bit 0 – DIR Counter Direction
This bit is used to change the direction of the counter.
Writing a '0' to this bit has no effect
Writing a '1' to this bit will clear the bit and make the counter count up.
| Value | Description |
|---|---|
| 0 | The timer/counter is counting up (incrementing). |
| 1 | The timer/counter is counting down (decrementing). |