m37905 Renesas Electronics Corporation., m37905 Datasheet - Page 165

• Manufacturer Part Number: m37905
• Description: Mitsubishi 16-bit Single-chip Microcomputer 7700 Family / 7900 Series
• Manufacturer: Renesas Electronics Corporation.

TIMER B
8.4 Event counter mode
Fig. 8.4.1 Structures of timer Bi register and timer Bi mode register in event counter mode
8-14
Timer B0 register (Addresses 51
Timer B1 register (Addresses 53
Timer B2 register (Addresses 55
Note: Reading from or writing to this register must be performed in a unit of 16 bits.
Timer Bi mode register (i = 0 to 2) (Addresses 5B
X : It may be either “0” or “1.”
Note: When the timer B2 clock source select bit (bit 6 at address 63
15 to 0 Any value in the range from “0000
Bit
Bit
0
1
2
3
4
5
6
7
edge of the external signal).
Assuming that the set value = n, the counter divides the count source frequency by (n + 1).
When reading, the register indicates the counter value.
Operating mode select bits
Count polarity select bits
This bit is invalid in event counter mode.
This bit is invalid in event counter mode; its value is undefined at reading.
These bits are invalid in event counter mode.
Bit name
16
16
16
, 50
, 52
, 54
7905 Group User’s Manual Rev.1.0
16
16
16
16
)
)
)
b1 b0
b3 b2
0 0 : Count at falling edge of external signal
0 1 : Count at rising edge of external signal
1 0 : Count at both falling and rising edges of external
1 1 : Do not select.
0 1 : Event counter mode
” to “FFFF
Function
signal
16
16
(b15)
” can be set.
to 5D
b7
16
) = “1,” be sure to fix these bits to “01
16
)
Function
(b8)
b0
b7
b7 b6 b5 b4 b3 b2 b1 b0
X X
(Note)
X
2
” (count at the rising
Undefined
X
At reset
Undefined
At reset
0
0
0
0
0
0
0
R/W
RW
R/W
0 1
RW
RW
RW
RW
RW
RW
RO
—
b0