M30622 Mitsubishi, M30622 Datasheet - Page 88

• Manufacturer Part Number: M30622
• Description: SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
• Manufacturer: Mitsubishi

Timer A
Table 1.17.2. Timer specifications in event counter mode (when not processing two-phase pulse signal)
Note 1: This does not apply when the free-run function is selected.
Note 2: M30623(80-pin package) does not have I/O pins(TAi
Figure 1.17.8. Timer Ai mode register in event counter mode
(2) Event counter mode
Count source
Count operation
Divide ratio
Count start condition
Count stop condition
Interrupt request generation timing The timer overflows or underflows
TAi
TAi
Read from timer
Write to timer
Select function
In this mode, the timer counts an external signal or an internal timer’s overflow. Timers A0 and A1 can
count a single-phase external signal. Timers A2, A3, and A4 can count a single-phase and a two-phase
external signal. Table 1.17.2 lists timer specifications when counting a single-phase external signal.
Figure 1.17.8 shows the timer Ai mode register in event counter mode.
Table 1.17.3 lists timer specifications when counting a two-phase external signal. Figure 1.17.9 shows
the timer Ai mode register in event counter mode.
IN
OUT
Tentative Specifications REV.A
pin function
pin function
S
Item
pecifications in this manual are tentative and subject to change.
Timer Ai mode register
b7
b6
b5
0
b4
b3
b2
• External signals input to TAi
• TB2 overflow, TAj overflow
• Up count or down count can be selected by external signal or software
• When the timer overflows or underflows, it reloads the reload register con
1/ (FFFF
1/ (n + 1) for down count
Count start flag is set (= 1)
Count start flag is reset (= 0)
Programmable I/O port or count source input
Programmable I/O port, pulse output, or up/down count select input
Count value can be read out by reading timer Ai register
• When counting stopped
• When counting in progress
• Free-run count function
• Pulse output function
b1
0 1
tents before continuing counting (Note)
When a value is written to timer Ai register, it is written to both reload register and counter
When a value is written to timer Ai register, it is written to only reload register
(Transferred to counter at next reload time)
Even when the timer overflows or underflows, the reload register content is not reloaded to it
Each time the timer overflows or underflows, the TAi
b0
Note 1: In event counter mode, the count source is selected by the event / trigger select bit
Note 2: The settings of the corresponding port register and port direction register are invalid.
Note 3: Valid only when counting an external signal.
Note 4: When an “L” signal is input to the TAi
Note 5: In Timer A1 and A2 mode register of M30623(80-pin package), set these bits to “0”.
Bit symbol
TMOD0
TMOD1
TCK0
TCK1
MR1
MR2
MR0
MR3
(addresses 0382
the upcount is activated. Set the corresponding port direction register to “0”.
16
Symbol
TAiMR(i = 0, 1)
- n + 1) for up count
Operation mode select bit
0 (Must always be fixed to “0” in event counter mode)
Pulse output function
select bit (Note 5)
Count polarity
select bit (Note 3,Note 5)
Up/down switching cause
select bit (Note 5)
Count operation type
select bit
Invalid in event counter mode
Can be “0” or “1”
Bit name
16
and 0383
0396
88
Address
16
, 0397
16
).
IN
Specification
16
b1 b0
0 1 : Event counter mode (Note 1)
0 : Pulse is not output
1 : Pulse is output (Note 2)
0 : Counts external signal's falling edge
1 : Counts external signal's rising edge
0 : Up/down flag's content
1 : TA
0 : Reload type
1 : Free-run type
pin (effective edge can be selected by software)
(TA
(TA
IN
OUT
When reset
iOUT
iOUT
iOUT
,TAi
00
pin, the downcount is activated. When “H”,
pin's input signal (Note 4)
n : Set value
16
pin is a normal port pin)
pin is a pulse output pin)
OUT
Function
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
) for timer A1 and A2.
OUT
R W
R
pin’s polarity is reversed
W
Mitsubishi microcomputers
M16C / 62T Group