TMP92CD54I Datasheet, PDF (118/343 Pages) Toshiba Semiconductor – 32-bit Micro-controller

TMP92CD54I
Count clock
(internal clock)
TI8 pin input
(external trigger pulse)
Match with TREG9
c
c+p
Load the up-counter value into
Capture Register (CAP8).
INT5 occurred
INTTR9
occurred
Load the up-counter value into
Capture Register (CAP9)
Timer output TO8
Enables inversion caused by
loading of the up-counter
value into CAP8.
Inversion
Pulse width
(p)
Disables incersioncaused by loading
of the up-counter value into CAP9.
Figure 3.8.13 One-shot pulse output (without delay)
d Frequency measurement
The frequency of the external clock can be measured in this mode. The clock is
input via the TI8 pin and its frequency is measured using the two 8-bit timers of
timers 01 and the 16-bit timer / event counter timer 8.
The TI8 pin input should be selected as the clock input to timer 8. Set
TMOD8<CAP89M1,CAP89M0> to 11. The value of the up-counter is loaded into
the capture register CAP8 on the rising edge of the TFF1 signal from the timer
flip-flop for the two 8-bit timers (timers 01), and loaded into CAP9 on the falling
edge of the TFF1 signal.
The frequency is calculated using the difference between the values loaded into
CAP8 and CAP9 when the interrupt (INTT0 or INTT1) is generated by either one
of the 8-bit timers.
Count clock
(TI8 input clock)
C8
C9
TFF1
Loading UC into CAP8
C8
Loading UC into CAP9
C8
C9
C9
INTT0/INTT1
Figure 3.8.14 Frequency Measurement
For example, if the value for the level 1 width of TFF1 of the 8-bit timer is set to
0.5 s and the difference between the values in CAP8 and CAP9 is 100, the
frequency is 100 ÷ 0.5 s = 200 Hz.
92CD54I-118
2006-01-27