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Under
development
Preliminary Specifications REV.D
Specifications in this manual are tentative and subject to change.
Mitsubishi Microcomputers
M16C/80 group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Usage precaution
207
Usage Precaution
SFR (100-pin version)
(1) Addresses 03C916, 03CB16 to 03D316 , 03DC16 area is for future plan. Must set "FF16" to address
03CB16, 03CE16, 03CF16, 03D216, 03D316 and "0016" to address 03DC16 at initial setting.
Timer A (timer mode)
(1) Reading the timer Ai register while a count is in progress allows reading, with arbitrary timing, the
value of the counter. Reading the timer Ai register with the reload timing gets “FFFF16”. Reading
the timer Ai register after setting a value in the timer Ai register with a count halted but before the
counter starts counting gets a proper value.
Timer A (event counter mode)
(1) Reading the timer Ai register while a count is in progress allows reading, with arbitrary timing, the
value of the counter. Reading the timer Ai register with the reload timing gets “FFFF16” by under-
flow or “000016” by overflow. Reading the timer Ai register after setting a value in the timer Ai
register with a count halted but before the counter starts counting gets a proper value.
(2) When stop counting in free run type, set timer again.
(3) In the case of using as “Free-Run type”, the timer register contents may be unknown when count-
ing begins. If the timer register is set before counting has started, then the starting value will be
unknown.
In the case where the up/down count will not be changed.
Enable the “Reload” function and write to the timer register before counting begins. Re-
write the value to the timer register immediately after counting has started. If counting
up, rewrite “000016” to the timer register. If counting down, rewrite “FFFF16” to the timer
register. This will cause the same operation as “Free-Run type” mode.
In the case where the up/down count has changed.
First set to “Reload type” operation. Once the first counting pulse has occurred, the timer
may be changed to “Free-Run type”.
Timer A (one-shot timer mode)
(1) Setting the count start flag to “0” while a count is in progress causes as follows:
The counter stops counting and a content of reload register is reloaded.
The TAiOUT pin outputs “L” level.
The interrupt request generated and the timer Ai interrupt request bit goes to “1”.
(2) The output from the one-shot timer synchronizes with the count source generated internally.
Therefore, when an external trigger has been selected, a delay of one cycle of count source as
maximum occurs between the trigger input to the TAiIN pin and the one-shot timer output.