deveopmen
Usage precaution
Preliminary Specifications REV.D
Specifications in this manual are tentative and subject to change.
Mitsubishi microcomputers
M16C/80 (100-pin version) group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
201
Usage Precaution
SFR
(1) Addresses 03C9
16
, 03CB
16
to 03D3
16
area is for future plan. Must set "FF
16
" to address 03CB
16
,
03CE
16
, 03CF
16
, 03D2
16
, 03D3
16
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 “FFFF
16
”. 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 “FFFF
16
” by under-
flow or “0000
16
” 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.
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 TAi
OUT
pin outputs “L” level.
The interrupt request generated and the timer Ai interrupt request bit goes to “1”.
(2) The timer Ai interrupt request bit goes to “1” if the timer's operation mode is set using any of the
following procedures:
Selecting one-shot timer mode after reset.
Changing operation mode from timer mode to one-shot timer mode.
Changing operation mode from event counter mode to one-shot timer mode.
Therefore, to use timer Ai interrupt (interrupt request bit), set timer Ai interrupt request bit to “0” after
the above listed changes have been made.
Timer A (pulse width modulation mode)
(1) The timer Ai interrupt request bit becomes “1” if setting operation mode of the timer in compliance
with any of the following procedures:
Selecting PWM mode after reset.
Changing operation mode from timer mode to PWM mode.
Changing operation mode from event counter mode to PWM mode.
Therefore, to use timer Ai interrupt (interrupt request bit), set timer Ai interrupt request bit to “0”
after the above listed changes have been made.
(2) Setting the count start flag to “0” while PWM pulses are being output causes the counter to stop
counting. If the TAi
OUT
pin is outputting an “H” level in this instance, the output level goes to “L”,
and the timer Ai interrupt request bit goes to “1”. If the TAi
OUT
pin is outputting an “L” level in this
instance, the level does not change, and the timer Ai interrupt request bit does not becomes “1”.