Timer/PWM Module (S08TPMV3)

pin is forced low at the start of each new period (TPMxCNT=0x0000), and the pin is forced high when the channel value register matches the timer counter.

TPMxMODH:TPMxMODL = 0x0008

TPMxMODH:TPMxMODL = 0x0005

TPMxCNTH:TPMxCNTL ... 0 1 2 3 4 5 6 7 8 0 1 2 ...

TPMxCHn

CHnF Bit

TOF Bit

Figure 17-3. High-True Pulse of an Edge-Aligned PWM

TPMxMODH:TPMxMODL = 0x0008

TPMxMODH:TPMxMODL = 0x0005

TPMxCNTH:TPMxCNTL ... 0 1 2 3 4 5 6 7 8 0 1 2 ...

TPMxCHn

CHnF Bit

TOF Bit

Figure 17-4. Low-True Pulse of an Edge-Aligned PWM

When the TPM is configured for center-aligned PWM and ELSnB:ELSnA are not cleared, the data direction for all channels in this TPM are overridden, the TPMxCHn pins are forced to be outputs controlled by the TPM, and the ELSnA bits control the polarity of each TPMxCHn output. If ELSnB is set and ELSnA is cleared, the corresponding TPMxCHn pin is negated when the timer counter is counting up, and the channel value register matches the timer counter. The TPMxCHn pin is asserted when the timer counter is counting down, and the channel value register matches the timer counter. If ELSnA is set, the corresponding TPMxCHn pin is asserted when the timer counter is counting up and the channel value register matches the timer counter; the TPMxCHn pin is negated when the timer counter is counting down and the channel value register matches the timer counter.

TPMxMODH:TPMxMODL = 0x0008

TPMxMODH:TPMxMODL = 0x0005

TPMxCNTH:TPMxCNTL ... 7 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 7 6

TPMxCHn

CHnF Bit

TOF Bit

5 ...

Figure 17-5. High-True Pulse of a Center-Aligned PWM

MCF51QE128 MCU Series Reference Manual, Rev. 3

340

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Freescale Semiconductor MCF51QE128RM manual High-True Pulse of an Edge-Aligned PWM