
PROGRAMMABLE TIMER
6-8
READ:
Any time.
WRITE:
Has no meaning or effect.
RESET:
Indeterminate (not initialized).
These registers are used to latch the value of timer counter 2 when a defined transition is sensed
by the corresponding input capture edge detector. The result obtained by an input capture
corresponds to the value of the counter one cycle after the transition which triggered the edge
detection logic. This delay is required for internal synchronization.
After a read of the most significant byte of the register, counter transfer is inhibited during the next
E-clock cycle. During double byte reads, this inhibited transfer will occur between consecutive read
cycles of the most and least significant bytes.
6.4.4
Output Compare Registers (TOC1 – TOC4)
BIT15
BIT14
BIT13
BIT12
BIT11
BIT10
BIT9
BIT8
TOC1
$1016
7
6
5
4
3
2
1
0
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
BIT1
BIT0
$1017
BIT15
BIT14
BIT13
BIT12
BIT11
BIT10
BIT9
BIT8
TOC2
$1018
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
BIT1
BIT0
$1019
BIT15
BIT14
BIT13
BIT12
BIT11
BIT10
BIT9
BIT8
TOC3
$101A
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
BIT1
BIT0
$101B
BIT15
BIT14
BIT13
BIT12
BIT11
BIT10
BIT9
BIT8
TOC4
$101C
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
BIT1
BIT0
$101D
READ:
Any time.
WRITE:
Any time.
RESET:
$FFFF
A write to a high order byte inhibits the compare for the next E-clock cycle. When the TOCx register
matches the TCNT1 register, the OCxF bit in the TFLG1 register is set and the specified output
action takes place.
All output compare registers have a separate dedicated comparator for comparing against the free
running counter. If a match is found, the corresponding output compare flag bit (OCxF) is set and
a specified action is automatically taken.
For output compare functions OC2, OC3 and OC4, the automatic action is controlled by pairs of bits
in the TCTL1 control register. Each pair of control bits is encoded to specify the output action to be
taken as a result of a successful OCx compare. Output compare functions OC2, OC3 and OC4 are
always associated with Port A bits 6 – 4 respectively.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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