m37905 Renesas Electronics Corporation., m37905 Datasheet - Page 464

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

Particular function select register 0
Particular function select register 1 (Address 63
Notes 1: At power-on reset, this bit becomes “0.” At hardware reset or software reset, this bit retains the value just before reset.
Note: Writing to these bits requires the following procedure:
7 to 2
Bit
Bit
0
1
0
1
2
3
4
5
6
7
• Write “55
• Succeedingly, write “0” or “1” to each bit.
Also, use the MOVMB (MOVM when m = 1) instruction or STAB (STA when m = 1) instruction.
If an interrupt occurs between writing of “55
possibility that an interrupt occurs at the above timing, be sure to read this bit’s contents after writing of “0” or “1,” and verify
whether “0” or “1” has correctly been written or not.
2: Even when “1” is written, the bit status will not change.
3: Setting this bit to “1” must be performed just before execution of the WIT instruction. Also, after the wait state is termi-
4: When using timer B2 in the pulse period/pulse width measurement mode, be sure to clear this bit to “0.”
nated, this bit must be cleared to “0” immediately.
STP instruction invalidity select bit
External clcok input select bit
Fix these bits to “000000.”
STP-instruction-execution
status bit
WIT-instruction-execution
status bit
Fix this bit to “0.”
System clock stop select bit
at WIT
Fix this bit to “0.”
The value is “0” at reading.
Timer B2 clock source select bit
(Valid in event counter mode.)
The value is “0” at reading.
16
” to this register. (The bit status does not change only by this writing.)
Bit name
Bit name
(Note 3)
(Note 4)
(Address 62
7905 Group User’s Manual Rev.1.0
0 : STP instruction is valid.
1 : STP instruction is invalid.
0 : Oscillation circuit is active. (Oscillator is connected.)
1 : Oscillation circuit is inactive. (External clock is
16
0 : External signal input to the TB2
1 : fX
0 : Normal operation.
1 : During execution of WIT instruction
0 : In the wait mode, system clock f
1 : In the wait mode, system clock f
0 : Normal operation.
1 : During execution of STP instruction
” and next writing of “0” or “1,” latter writing may be ignored. When there is a
Watchdog timer is used at stop mode termination.
When the system clock select bit (bit 5 at address BC
watchdog timer is not used at stop mode termination.
When the system clock select bit = “1,”
watchdog timer is used at stop mode termination.
input.)
32
16
is counted.
16
)
)
Function
Function
IN
Appendix 2. Control registers
pin is counted.
sys
sys
is active.
is inactive.
b7 b6 b5 b4 b3 b2 b1 b0
b7 b6 b5 b4 b3 b2 b1 b0
0
16
0
) = “0,”
0
0
0
At reset
(Note 1)
(Note 1)
At reset
0 0
0
0
0
APPENDIX
0
0
0
0
0
0
0
(Note 2)
(Note 2)
(Note)
(Note)
R/W
RW
RW
RW
R/W
RW
RW
RW
RW
RW
RW
—
—
Reference
Reference
15-4
4-10
15-5
16-4
15-6
16-5
8-15
20-33