tmp89fm42 TOSHIBA Semiconductor CORPORATION, tmp89fm42 Datasheet - Page 166

• Manufacturer Part Number: tmp89fm42
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

13.4 Timer Function
13. 16-bit Timer Counter (TCA)
RA001
13.4.2 External trigger timer mode
13.4.2.1 Setting
13.4.2.2 Operation
13.4.2.3 Auto capture
13.4.2.4 Register buffer configuration
TCA0 pin.
In the external trigger timer mode, the up counter starts counting when it is triggered by the input to the
mode. Select the source clock at TA0MOD<TA0CK>.
TA0MOD<TA0TED> to "0" selects the rising edge, and setting it to "1" selects the falling edge.
in port settings.
TA0MOD and TA0CR<TA0OVE> is disabled. Be sure to complete the required mode settings before
starting the timer.
ments according to the selected source clock. When a match between the up counter value and the value
set to timer register A (TA0DRA) is detected, an INTTA0 interrupt request is generated and the up counter
is cleared to "0000H". After being cleared, the up counter continues counting.
up counter stops counting and is cleared to "0000H". Subsequently, when the selected trigger edge is
detected, the up counter restarts counting. In this mode, an interrupt request can be generated by detecting
that the input pulse exceeds a certain pulse width. If TA0MOD<TA0METT> is "0", the detection of the
selected edge and the opposite edge is ignored during the period from the detection of the specified trigger
edge and the start of counting through until the match detection.
cleared to "0000H".
Setting the operation mode selection TA0MOD<TA0M> to "100" activates the external trigger timer
Select the trigger edge at the trigger edge input selection TA0MOD<TA0TED>. Setting
Note that this mode uses the TA0 input pin, and the TCA0 pin must be set to the input mode beforehand
The operation is started by setting TA0CR<TA0S> to "1". After the timer is started, writing to
After the timer is started, when the selected trigger edge is input to the TCA0 pin, the up counter incre-
When TA0MOD<TA0METT> is "1" and the edge opposite to the selected trigger edge is detected, the
Setting TA0CR<TA0S> to "0" during the timer operation causes the up counter to stop counting and be
Refer to "13.4.1.3 Auto capture".
Refer to "13.4.1.4 Register buffer configuration".
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