MITSUBISHI MICROCOMPUTERS
M37754M8C-XXXGP, M37754M8C-XXXHP
M37754S4CGP, M37754S4CHP
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
When bit 5 is “0, counting restarts from the value which is contained
Pulse output function
at restarting (gate function 0 [no reload]) and an overflow occurs (n +
1) cycles of the count source later. Figure 21 shows that operation.
When bit 5 is “1”, counting restarts from the value which is obtained
by reload at restarting (gate function 1 [reload]) and the first overflow
occurs (n + 2) cycles of the count source later. Figure 22 shows that
operation. After that, while the input signal from the TAiIN pin keeps
valid level, an overflow occurs at (n + 1)- cycle intervals. Make sure
to set the value of 1 or more to n.
When bit 2 of the timer Ai mode register is “1”, the output is gener-
ated from TAiOUT pin. The output is toggled each time the contents of
the counter reaches to 000016. When the contents of the count start
bit is “0”, “L” is output from TAiOUT pin.
When bit 2 is “0”, TAiOUT can be used as a normal port pin. When bit
4 is “0”, TAiIN can be used as a normal port pin.
Gate function
When gate functions are used, the duration of “H” or “L” on the TAiIN
pin must be 2 or more cycles of the timer count source.
When bit 4 is “1”, counting is performed only while the input signal
from the TAiIN pin is “H” or “L” as shown in Figure 20. Therefore, this
can be used to measure the pulse width of the TAiIN input signal.
Whether to count while the input signal is “H” or while it is “L” is de-
termined by bit 3. If bit 3 is “1”, counting is performed while the TAiIN
pin input signal is “H” and if bit 3 is “0”, counting is performed while it
is “L”.
Addresses
Timer A0 mode register
Timer A1 mode register
Timer A2 mode register
Timer A3 mode register
Timer A4 mode register
5616
5716
5816
5916
5A16
7
6
5
4
3
2
1
0
0
0
0 0 : Always “00” in timer mode
0 : No pulse output (TAiOUT is normal port pin)
1 : Pulse output
0
× : No gate function (TAiIN is normal port pin)
1 0 : Count only while TAiIN input is “L”
1 1 : Count only while TAiIN input is “H”
0 : Gate function 0 (No reload)
1 : Gate function 1 (Reload) ; Note
Clock source select bit
0 0 : Select Pf
2
0 1 : Select Pf16
1 0 : Select Pf64
1 1 : Select Pf512
Note: When selecting no gate function (bit 4 = “0”) in timer mode, fix bit 5 to “0”.
Fig. 18 Timer Ai mode register bit configuration during timer mode
24
RENESAS [ RENESAS TECHNOLOGY CORP ]
