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8.4 Registers of 8/16-bit Capture Timer/Counter
8.4.6
Timer 1 Data Register (TDR1)
The timer 1 data register (TDR1) is used to set the timer 1 value in the 8-bit mode of the
8/16-bit capture timer/counter or the interval timer value (interval timer function) or
counter value (counter function) of the higher 8 bits in the 16-bit mode.
s Timer 1 Data Register (TDR1)
The values set in this register are compared with those set in the counter.
Figure 8.4-7 "Bit Structure of Timer 1 Data Register (TDR1)" shows the bit structure of timer 1
data register (TDR1).
Figure 8.4-7 Bit Structure of Timer 1 Data Register (TDR1)
r 8-bit mode (timer 1)
The values set in this register are compared with those set in the counter. When the interval
timer function is used, an interval timer value is set. When the counter function is used, the
count value to be detected is set. The values in TDR1 are reset in (loaded to) the comparator
data latch when they match the values in the counter or when the count operation is started.
The values written to TDR1 when the counter is operating become valid from the next cycle
(after match detection).
Tip:
The values set in TDR1 when the interval timer is operating can be calculated from the
expression shown below. However, the instruction cycle is affected by the clock mode and
gear function.
Values set in TDR1 = interval time/(count clock cycle x instruction cycle) - 1
r 16-bit mode
The values in TDR1 are compared with the counter values in the higher 8 bits of the 16-bit
timer.
When the interval timer function is used, the higher 8 bits of the interval time are set. When the
counter function is used, the higher 8 bits of the count value to be detected are set. The values
in TDR1 are loaded to the higher 8 bits of the comparator data latch when matching the counter
values of the 16-bit timer or when the count operation is started. The values written to TDR1
when the 16-bit counter is operating become valid after match detection. In the 16-bit mode, the
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
R/W
R/W : Readable and Writable
X
: Undefined
Address
Initial value
001CH
XXXXXXXXB