S9S12XS256J0CAL Datasheet, PDF (371/738 Pages) Freescale Semiconductor, Inc – Microcontrollers

Pulse-Width Modulator (S12PWM8B8CV1)
NOTE
The first PWM cycle after enabling the channel can be irregular.
An exception to this is when channels are concatenated. Once concatenated mode is enabled (CONxx bits
set in PWMCTL register), enabling/disabling the corresponding 16-bit PWM channel is controlled by the
low order PWMEx bit.In this case, the high order bytes PWMEx bits have no effect and their
corresponding PWM output lines are disabled.
While in run mode, if all eight PWM channels are disabled (PWME7–0 = 0), the prescaler counter shuts
off for power savings.
Module Base + 0x0000
R
W
Reset
7
PWME7
0
6
PWME6
5
PWME5
4
PWME4
3
PWME3
2
PWME2
0
0
0
0
0
Figure 13-3. PWM Enable Register (PWME)
1
PWME1
0
0
PWME0
0
Read: Anytime
Write: Anytime
Table 13-1. PWME Field Descriptions
Field
7
PWME7
6
PWME6
5
PWME5
4
PWME4
3
PWME3
2
PWME2
Description
Pulse Width Channel 7 Enable
0 Pulse width channel 7 is disabled.
1 Pulse width channel 7 is enabled. The pulse modulated signal becomes available at PWM output bit 7 when
its clock source begins its next cycle.
Pulse Width Channel 6 Enable
0 Pulse width channel 6 is disabled.
1 Pulse width channel 6 is enabled. The pulse modulated signal becomes available at PWM output bit6 when
its clock source begins its next cycle. If CON67=1, then bit has no effect and PWM output line 6 is disabled.
Pulse Width Channel 5 Enable
0 Pulse width channel 5 is disabled.
1 Pulse width channel 5 is enabled. The pulse modulated signal becomes available at PWM output bit 5 when
its clock source begins its next cycle.
Pulse Width Channel 4 Enable
0 Pulse width channel 4 is disabled.
1 Pulse width channel 4 is enabled. The pulse modulated signal becomes available at PWM, output bit 4 when
its clock source begins its next cycle. If CON45 = 1, then bit has no effect and PWM output bit4 is disabled.
Pulse Width Channel 3 Enable
0 Pulse width channel 3 is disabled.
1 Pulse width channel 3 is enabled. The pulse modulated signal becomes available at PWM, output bit 3 when
its clock source begins its next cycle.
Pulse Width Channel 2 Enable
0 Pulse width channel 2 is disabled.
1 Pulse width channel 2 is enabled. The pulse modulated signal becomes available at PWM, output bit 2 when
its clock source begins its next cycle. If CON23 = 1, then bit has no effect and PWM output bit2 is disabled.
S12XS Family Reference Manual, Rev. 1.13
Freescale Semiconductor
371