General Purpose Timer Module (GPT)
MCF52235 ColdFire® Integrated Microcontroller Reference Manual, Rev. 6
Freescale Semiconductor
23-13
23.6.14 GPT Channel Registers (GPTCn)
23.6.15 Pulse Accumulator Control Register (GPTPACTL)
IPSBAR
Offsets:
0x1A_0010, 0x1A_0012, 0x1A_0014, 0x1A_0016, (GPTCn)
Access: Supervisor
read/write
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R
CCNT
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 23-16. GPT Channel[0:3] Register (GPTCn)
Table 23-17. GPTCn Field Descriptions
Field
Description
15–0
CCNT
When a channel is configured for input capture (IOSn = 0), the GPT channel registers latch the value of the
free-running counter when a defined transition occurs on the corresponding input capture pin.
When a channel is configured for output compare (IOSn = 1), the GPT channel registers contain the output compare
value.
To ensure coherent reading of the GPT counter, such that a timer rollover does not occur between back-to-back 8-bit
reads, it is recommended that only word (16-bit) accesses be used. These bits are read anytime, write anytime (for
the output compare channel); writing to the input capture channel has no effect.
IPSBAR
Offsets: 0x1A_0018 (GPTPACTL)
Access: Supervisor read/write
7
6
5
4
3
2
1
0
R
0
PAE
PAMOD
PEDGE
CLK
PAOVI
PAI
W
Reset:
0
0
0
0
0
0
0
0
Figure 23-17. Pulse Accumulator Control Register (GPTPACTL)
Table 23-18. GPTPACTL Field Descriptions
Field
Description
7
Reserved, should be cleared.
6
PAE
Enables the pulse accumulator.
1 Pulse accumulator enabled
0 Pulse accumulator disabled
Note: The pulse accumulator can operate in event mode even when the GPT enable bit, GPTEN, is clear.
5
PAMOD
Pulse accumulator mode. Selects event counter mode or gated time accumulation mode.
1 Gated time accumulation mode
0 Event counter mode
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:MCF52234CVM60,
MCF52235CVM60