7702 Datasheet, PDF (466/522 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER

APPENDIX
Appendix 3. Control registers
Event counter mode
b7 b6 b5 b4 b3 b2 b1 b0
!! 0
0 1 Timer Ai mode register (i = 0 to 4) (Addresses 5616 to 5A16)
Bit
Bit name
0 Operating mode select bits
1
Functions
b1 b0
0 1 : Event counter mode
At reset _RW
0 RW
0 RW
2 Pulse output function select bit 0 : No pulse output (TAiOUT pin functions 0
RW
as a programmable I/O port.)
1 : Pulse output (TAiOUT pin functions
as a pulse output pin.)
3 Count polarity select bit
0 : Counts at falling edge of external signal
0
RW
1 : Counts at rising edge of external signal
4 Up-down switching factor select 0 : Contents of up-down register
bit
1 : Input signal to TAiOUT pin
5 Fix this bit to “0” in event counter mode.
0 RW
0 RW
6 These bits are ignored in event counter mode.
0 RW
7
! : It may be either “0” or “1.”
0 RW
(b15)
b7
(b8)
b0 b7
b0
Timer A0 register (Addresses 4716, 4616)
Timer A1 register (Addresses 4916, 4816)
Timer A2 register (Addresses 4B16, 4A16)
Timer A3 register (Addresses 4D16, 4C16)
Timer A4 register (Addresses 4F16, 4E16)
Bit
Functions
At reset RW
15 to 0 These bits can be set to “000016” to “FFFF16.” _{Undefined RW}
Assuming that the set value = n, the counter
divides the count source frequency by n + 1
when down-counting, or by FFFF16 – n + 1
when up-counting.
When reading, the register indicates the
counter value.
21–22
7702/7703 Group User’s Manual