DMA Timers (DTIM0–DTIM3)
Freescale Semiconductor
24-7
MCF52235 ColdFire® Integrated Microcontroller Reference Manual, Rev. 6
24.2.4
DMA Timer Reference Registers (DTRRn)
As part of the output-compare function, each DTRR
n
contains the reference value compared with the
respective free-running timer counter (DTCN
n
).
The reference value is matched when DTCN
n
equals DTRR
n
. The prescaler indicates that DTCN
n
should
be incremented again. Therefore, the reference register is matched after DTRR
n
+ 1 time intervals.
24.2.5
DMA Timer Capture Registers (DTCRn)
Each DTCR
n
latches the corresponding DTCN
n
value during a capture operation when an edge occurs on
DTIN
n
, as programmed in DTMR
n
. The internal bus clock is assumed to be the clock source. DTIN
n
cannot simultaneously function as a clocking source and as an input capture pin. Indeterminate operation
results if DTIN
n
is set as the clock source when the input capture mode is used.
IPSBAR
Offset:
0x00_0404 (DTRR0)
0x00_0444 (DTRR1)
0x00_0484 (DTRR2)
0x00_04C4 (DTRR3)
Access: User read/write
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
R
REF (32-bit reference value)
W
Reset 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Figure 24-5. DTRRn Registers
Table 24-5. DTRRn Field Descriptions
Field
Description
31–0
REF
Reference value compared with the respective free-running timer counter (DTCNn) as part of the output-compare
function.
IPSBAR
Offset:
0x00_0408
(
DTCR0
)
0x00_0448
(
DTCR1
)
0x00_0488
(
DTCR2
)
0x00_04C8
(
DTCR3
)
Access: User read-only
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
R
CAP (32-bit capture counter value)
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Figure 24-6. DTCRn Registers
Table 24-6. DTCRn Field Descriptions
Field
Description
31–0
CAP
Captures the corresponding DTCNn value during a capture operation when an edge occurs on DTIN
n
, as
programmed in DTMRn.
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
