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Chapter 20 Pulse Width Modulator with Fault Protection (PMF15B6C) Module
MC9S12XF - Family Reference Manual, Rev.1.19
918
Freescale Semiconductor
NOTE
The IPOLx bits take effect at the beginning of the next load cycle, regardless
of the state of the load okay bit, LDOK. Select top/bottom software
correction by writing 01 to the current select bits, ISENS[1:0], in the PWM
control register. Reading the IPOLx bits read the buffered value and not
necessarily the value currently in effect.
20.3.2.14 PMF Value 0 Register (PMFVAL0)
Read and write anytime.
20.3.2.15 PMF Value 1 Register (PMFVAL1)
11
Current status sample on pins IS0, IS1, and IS2(3)
At the half cycle in center-aligned operation
At the end of the cycle in edge-aligned operation
1. The current status pins can be used as general purpose input/output ports.
2. The polarity of the ISx pin is latched when both the top and bottom PWMs are off. At the 0% and
100% duty cycle boundaries, there is no deadtime, so no new current value is sensed.
3. Current is sensed even with 0% or 100% duty cycle.
Address: $0010
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R
PMFVAL0
W
Reset
0
0000000
Figure 20-20. PMF Value 0 Register (PMFVAL0)
Table 20-18. PMFVAL0 Field Descriptions
Field
Description
15–0
PMFVAL0
PMF Value 0 Bits — The 16-bit signed value in this buffered register is the pulse width in PWM0 clock period.
A value less than or equal to zero deactivates the PWM output for the entire PWM period. A value greater than,
or equal to the modulus, activates the PWM output for the entire PWM period. See Table 20-36. The terms
activate and deactivate refer to the high and low logic states of the PWM output.
Note: PMFVAL0 is buffered. The value written does not take effect until the LDOK bit is set and the next PWM
load cycle begins Reading PMFVAL0 reads the value in the buffer and not necessarily the value the PWM
generator is currently using.
Address: $0012
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R
PMFVAL1
W
Reset
0
0000000
Figure 20-21. PMF Value 1 Register (PMFVAL1)
Table 20-17. Correction Method Selection
ISENS
Correction Method