M30222 Datasheet, PDF (76/237 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

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MITSUBISHI MICROCOMPUTERS
Specifications in this manual are tentative and subject to change
M30222 Group
Rev. G
Timer A
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Table 1.27. Timer specifications in event counter mode (when processing two-phase pulse signal with
Timers A2, A3,and A4)
Item
Count source
Count operation
Specification
• Two-phase pulse signals input to TAi IN or TAi OUT pin
• Up count or down count can be selected by two-phase pulse signal
• When the timer overflows or underflows, the reload register content is
reloaded and the timer starts over again (Note)
Divide ratio
1/ (FFFF16 - n + 1) for up count
1/ (n + 1) for down count
n : Set value
Count start condition
Count start flag is set (= 1)
Count stop condition
Count start flag is reset (= 0)
Interrupt request generation timing Timer overflows or underflows
TAi IN pin function
Two-phase pulse input
TAi OUT pin function
Two-phase pulse input
Read from timer
Count value can be read out by reading Timer A2, A3, or A4 register
Write to timer
• When counting stopped
When a value is written to Timer A2, A3, or A4 register, it is written to both
reload register and counter
• When counting in progress
When a value is written to Timer A2, A3, or A4 register, it is written to only
reload register. (Transferred to counter at next reload time.)
Select function
• Normal processing operation
The timer counts up rising edges or counts down falling edges on the TAi IN
pin when input signal on the TAi OUT pin is “H”
TAi OUT
TAi IN
(i=2,3)
Up
Count
Up
Count
Up
Count
Down
Count
Down
Count
Down
Count
• Multiply-by-4 processing operation
If the phase relationship is such that the TAi IN pin goes “H” when the input
signal on the TAi OUT pin is “H”, the timer counts up rising and falling edges
on the TAi OUT and TAi IN pins. If the phase relationship is such that the
TAi IN pin goes “L” when the input signal on the TAiOUT pin is “H”, the timer
counts down rising and falling edges on the TAiOUT and TAiIN pins.
TAiOUT
Count up all edges
TAiIN (i=3,4)
Count up all edges
Note: This does not apply when the free-run function is selected
Count down all edges
Count down all edges
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