Chapter 22 Timer Module (TIM16B8CV2) Block Description
MC9S12XE-Family Reference Manual Rev. 1.19
Freescale Semiconductor
797
22.3.2.6
Timer System Control Register 1 (TSCR1)
Read: Anytime
Write: Anytime
Module Base + 0x0006
7
6
5
4
3
2
1
0
R
TEN
TSWAI
TSFRZ
TFFCA
PRNT
0
0
0
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 22-12. Timer System Control Register 1 (TSCR2)
Table 22-6. TSCR1 Field Descriptions
Field
Description
7
TEN
Timer Enable
0 Disables the main timer, including the counter. Can be used for reducing power consumption.
1 Allows the timer to function normally.
If for any reason the timer is not active, there is no
÷
64 clock for the pulse accumulator because the
÷
64 is
generated by the timer prescaler.
6
TSWAI
Timer Module Stops While in Wait
0 Allows the timer module to continue running during wait.
1 Disables the timer module when the MCU is in the wait mode. Timer interrupts cannot be used to get the MCU
out of wait.
TSWAI also affects pulse accumulator.
5
TSFRZ
Timer Stops While in Freeze Mode
0 Allows the timer counter to continue running while in freeze mode.
1 Disables the timer counter whenever the MCU is in freeze mode. This is useful for emulation.
TSFRZ does not stop the pulse accumulator.
4
TFFCA
Timer Fast Flag Clear All
0 Allows the timer flag clearing to function normally.
1 For TFLG1(0x000E), a read from an input capture or a write to the output compare channel (0x0010–0x001F)
causes the corresponding channel flag, CnF, to be cleared. For TFLG2 (0x000F), any access to the TCNT
register (0x0004, 0x0005) clears the TOF flag. Any access to the PACNT registers (0x0022, 0x0023) clears
the PAOVF and PAIF flags in the PAFLG register (0x0021). This has the advantage of eliminating software
overhead in a separate clear sequence. Extra care is required to avoid accidental flag clearing due to
unintended accesses.
3
PRNT
Precision Timer
0 Enables legacy timer. PR0, PR1, and PR2 bits of the TSCR2 register are used for timer counter prescaler
selection.
1 Enables precision timer. All bits of the PTPSR register are used for Precision Timer Prescaler Selection, and
all bits.
This bit is writable only once out of reset.
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:
S12XE
products
in
208
MAPBGA
packages