Chapter 9 Pulse-Width Modulator (S12PWM8B8CV2)
S12ZVHY/S12ZVHL Family Reference Manual Rev. 1.05
Freescale Semiconductor
351
In concatenated mode, writes to the 16-bit counter by using a 16-bit access or writes to either the low or
high order byte of the counter will reset the 16-bit counter. Reads of the 16-bit counter must be made by
16-bit access to maintain data coherency.
Either left aligned or center aligned output mode can be used in concatenated mode and is controlled by
the low order CAEx bit. The high order CAEx bit has no effect.
is used to summarize which channels are used to set the various control bits when in 16-bit
mode.
9.4.2.8
PWM Boundary Cases
summarizes the boundary conditions for the PWM regardless of the output mode (left aligned
or center aligned) and 8-bit (normal) or 16-bit (concatenation).
9.5
Resets
The reset state of each individual bit is listed within the
Section 9.3.2, “Register Descriptions”
which
details the registers and their bit-fields. All special functions or modes which are initialized during or just
following reset are described within this section.
•
The 8-bit up/down counter is configured as an up counter out of reset.
•
All the channels are disabled and all the counters do not count.
Table 9-13. 16-bit Concatenation Mode Summary
Note:
Bits related to available channels have functional significance.
CONxx
PWMEx
PPOLx
PCLKx
CAEx
PWMx
Output
CON67
PWME7
PPOL7
PCLK7
CAE7
PWM7
CON45
PWME5
PPOL5
PCLK5
CAE5
PWM5
CON23
PWME3
PPOL3
PCLK3
CAE3
PWM3
CON01
PWME1
PPOL1
PCLK1
CAE1
PWM1
Table 9-14. PWM Boundary Cases
PWMDTYx
PWMPERx
PPOLx
PWMx Output
$00
(indicates no duty)
>$00
1
Always low
$00
(indicates no duty)
>$00
0
Always high
XX
$00
(1)
(indicates no period)
1. Counter = $00 and does not count.
1
Always high
XX
$00
1
(indicates no period)
0
Always low
>= PWMPERx
XX
1
Always high
>= PWMPERx
XX
0
Always low
