tmp19a61f10xbg TOSHIBA Semiconductor CORPORATION, tmp19a61f10xbg Datasheet - Page 294

• Manufacturer Part Number: tmp19a61f10xbg
• Description: 32-bit Tx System Risc Tx19 Family
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Prescaler output
clock
TBxxIN0 pin input
(External pulse)
Taking data into TBxxCP0H/L
Taking data into TBxxCP1H/L
INTCPTxx
(Note) INTCPTxx interruption is generated when the value of the up-counter is taken into
the capture register TBxxCP1H/L.
Pulse width measurement
By using the capture function, the “H” level width of an external pulse can be measured.
Specifically, by putting it in a free-running state using the prescaler output clock, an
external pulse is input through the TBxxIN1 pin and the up-counter (UC5) is made to
count up. A trigger is generated at each rising and falling edge of the external pulse by
using the capture function and the value of the up-counter is taken into the capture
registers (TBxxCP0H/L, TBxxCP1H/L). The INTC must be programmed so that
INTCPTxx is generated at the falling edge of the TBxxIN1 pin.
The “H” level pulse width can be calculated by multiplying the difference between
TBxxCP0H/L and TBxxCP1H/L by the clock cycle of an internal clock.
For example, if the difference between TBxxCP0H/L and TBxxCP1H/L is 100 and the
cycle of the prescaler output clock is 0.5 u s, the pulse width is 100 × 0.5 u s = 50 u s.
Caution must be exercised when measuring pulse widths exceeding the UC0
maximum count time which is dependant upon the source clock used. The
measurement of such pulse widths must be made using software.
The “L” level width of an external pulse can also be measured. In such cases, the
difference between C2 generated the first time and C1 generated the second time is
initially obtained by performing the second stage of INTCPT interrupt processing as
shown in “Fig. 11.4.4.5 Time Difference Measurement” and this difference is multiplied
by the cycle of the prescaler output clock.
C1
Fig. 11.4.4.4 Pulse Width Measurement
C1
TMP19A61 (rev 1.0)11-293
C2
C2
C1
TMP19A61
C2