Chapter 12 Pulse-Width Modulator (S12PWM8B8CV1)
MC9S12XDP512 Data Sheet, Rev. 2.11
574 Freescale Semiconductor
NOTE
When PWMSCLA = $00, PWMSCLA value is considered a full scale value
of 256. Clock A is thus divided by 512.
Any value written to this register will cause the scale counter to load the new scale value (PWMSCLA).
Read: Anytime
Write: Anytime (causes the scale counter to load the PWMSCLA value)
12.3.2.10 PWM Scale B Register (PWMSCLB)
PWMSCLB is the programmable scale value used in scaling clock B to generate clock SB. Clock SB is
generated by taking clock B, dividing it by the value in the PWMSCLB register and dividing that by two.
Clock SB = Clock B / (2 * PWMSCLB)
NOTE
When PWMSCLB = $00, PWMSCLB value is considered a full scale value
of 256. Clock B is thus divided by 512.
Any value written to this register will cause the scale counter to load the new scale value (PWMSCLB).
Read: Anytime
Write: Anytime (causes the scale counter to load the PWMSCLB value).
12.3.2.11 Reserved Registers (PWMSCNTx)
The registers PWMSCNTA and PWMSCNTB are reserved for factory testing of the PWM module and are
not available in normal modes.
Module Base + 0x0008
76543210
RBit 7 6 5 4 3 2 1 Bit 0
W
Reset 00000000
Figure 12-11. PWM Scale A Register (PWMSCLA)
Module Base + 0x0009
76543210
RBit 7 6 5 4 3 2 1 Bit 0
W
Reset 00000000
Figure 12-12. PWM Scale B Register (PWMSCLB)