
Under
1-78
Specifications in this manual are tentative and subject to change
Rev. G
Timer A
MITSUBISHI MICROCOMPUTERS
M30222 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Fig. 1.53. Timer Ai mode register in event counter mode
Note 1: The settings of the corresponding port register and port direction register are invalid.
Note 2: This bit is valid when only counting an external signal.
Note 3: Set the corresponding port direction register to
“
0
”
.
Note 4: This bit is valid for the timer A3 mode register.
For timer A2 and A4 mode registers, this bit can be
“
0
”
or
“
1
”
.
Note 5: When performing two-phase pulse signal processing, make sure the two-phase pulse
signal processing operation select bit (address 0384
16
) is set to
“
1
”
. Also, always be
sure to set the event/trigger select bit (addresses 0382
16
and 0383
16
) to
“
00
”
.
Timer Ai mode register
(When not using two-phase pulse signal processing)
Symbol
TAiMR(i = 2 to 4) 0398
16
to 039A
16
Address
When reset
00
16
b7
b6
b5
0
b4
b3
b2
b1
0
b0
1
Operation mode select bit
0 1 : Event counter mode
b1 b0
TMOD1
TMOD0
MR0
Pulse output function
select bit
0 : Pulse is not output
(TAi
OUT
pin is a normal port pin)
1 : Pulse is output (Note 1)
(TAi
OUT
pin is a pulse output pin)
0 : Counts external signal's falling edges
1 : Counts external signal's rising edges
Count polarity
select bit (Note 2)
MR2
MR1
MR3
0 : (Must always be
“
0
”
in event counter mode)
TCK1
TCK0
Up/down switching
cause select bit
0 : Up/down flag's content
1 : TA
iOUT
pin's input signal (Note 3)
Bit symbol
Bit name
Function
W
R
Count operation type
select bit
Two-phase pulse signal
processing operation
select bit (Note 4)(Note 5)
0 : Reload type
1 : Free-run type
0 : Normal processing operation
1 : Multiply-by-4 processing operation
Note 1: This bit is valid for TimerA3 mode register.
For Timer A2 and A4 mode registers, his bit can be
“
0
”
or
“
1
”
.
Note 2: When performing two-phase pulse signal processing, make sure the two-phase
pulse signal processing operation select bit (address 0384
16
) is set to "1".
Always be sure to set the event/trigger select bit (address 0382
16
) to "00".
Timer Ai mode register
(When using two-phase pulse signal processing)
Symbol
TAiMR(i = 2 to 4) 0398
16
to 039A
16
Address
When reset
00
16
b7
b6
b5
0
b4
1
b3
0
b2
0
b1
0
b0
1
Operation mode select bit
0 1 : Event counter mode
b1 b0
TMOD1
TMOD0
MR0
0 (Must always be
“
0
”
when using two-phase pulse signal
processing)
0 (Must always be
“
0
”
when using two-phase pulse signal
processing)
1 (Must always be
“
1
”
when using two-phase pulse signal
processing)
MR2
MR1
MR3
0 (Must always be
“
0
”
when using two-phase pulse signal
processing)
Count operation type
select bit
1 : Free-run type
TCK1
TCK0
Bit symbol
Bit name
Function
W
R
Two-phase pulse
processing operation
select bit (Note 1)(Note 2)
0 : Reload type
0 : Normal processing operation
1 : Multiply-by-4 processing operation