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CP3
BT26
27.2.2
I/O Control Register 1 (IO1CTL)
The I/O Control Register 1 (IO1CTL) is a word-wide read/
write register. The register controls the function of the I/O
pins TIO1 through TIO4 depending on the selected mode of
operation. The register is clear after reset.
CxEDG
The Capture Edge Control field specifies the
polarity of a capture event and the reset of the
counter. The value of this three bit field has no
effect while operating in PWM mode.
PxPOL
The PWM Polarity bit selects the output polar-
ity. While operating in PWM mode the bit
specifies the polarity of the corresponding
PWM output (TIOx). Once a counter is
stopped, the output will assume the value of
PxPOL, i.e., its initial value. The PxPOL bit
has no effect while operating in capture mode.
0 – The PWM output goes high at the 00h to
01h transition of the counter and will go
low once the counter value matches the
duty cycle value.
1 – The PWM output goes low at the 00h to
01h transition of the counter and will go
high once the counter value matches the
duty cycle value.
27.2.3
I/O Control Register 2 (IO2CTL)
The IO2CTL register is a word-wide read/write register. The
register controls the functionality of the I/O pins TIO5
through TIO8 depending on the selected mode of operation.
The register is cleared at reset.
The functionality of the bit fields of the IO2CTL register is
identical to the ones described in the IO1CTL register sec-
tion.
27.2.4
Interrupt Control Register (INTCTL)
The INTCTL register is a word-wide read/write register. It
contains the interrupt enable bits for all 16 interrupt sources
of the VTU. Each interrupt enable bit corresponds to an in-
terrupt pending bit located in the Interrupt Pending Register
(INTPND). All INTCTL register bits are solely under soft-
ware control. The register is clear after reset.
IxAEN
The Timer x Interrupt A Enable bit controls in-
terrupt requests triggered on the correspond-
ing IxAPD bit being set. The associated
IxAPD bit will be updated regardless of the
value of the IxAEN bit.
0 – Disable system interrupt request for the
IxAPD pending bit.
1 – Enable system interrupt request for the Ix-
APD pending bit.
IxBEN
The Timer x Interrupt B Enable bit controls in-
terrupt requests triggered on the correspond-
ing IxBPD bit being set. The associated
IxBPD bit will be updated regardless of the
value of the IxBEN bit.
0 – Disable system interrupt request for the
IxBPD pending bit.
1 – Enable system interrupt request for the Ix-
BPD pending bit.
7
6
4
3
2
0
P2POL
C2EDG
P1POL
C1EDG
15
14
12
11
10
8
P4POL
C4EDG
P3POL
C3EDG
CxEDG
Capture
Counter Reset
000
Rising edge
No
001
Falling edge
No
010
Rising edge
Yes
011
Falling edge
Yes
100
Both edges
No
101
Both edges
Rising edge
110
Both edges
Falling edge
111
Both edges
Both edges
7
6
4
3
2
0
P6POL
C6EDG
P5POL
C5EDG
15
14
12
11
10
8
P8POL
C8EDG
P7POL
C7EDG
7
6
5
4
3
2
1
0
I2DEN I2CEN I2BEN I2AEN I1DEN I1CEN I1BEN I1AEN
15
14
13
12
11
10
9
8
I4DEN I4CEN I4BEN I4AEN I3DEN I3CEN I3BEN I3AEN