APPENDIX
Appendix 2. Control registers
b7
b0
Particular function select register 2 (Address 6416
)
Bit
Function
At reset
R/W
Reference
Disables the watchdog timer.
When values of “7916” and “5016” succeedingly in this order, the watchdog timer will
14-4
7 to 0
—
Undefined
stop its operation.
Note: After reset, this register can be set only once. Writing to this register requires the following procedure:
• Write values of “7916” and “5016” to this register succeedingly in this order.
• For the above writing, be sure to use the MOVMB (MOVM when m = 1) instruction or the STAB (STA when m = 1).
Note that the following: if an interrupt occurs between writing of “7916” and next writing of “5016,” the watchdog timer does not
stop its operation.
If any of the following has been performed after reset, writing to this register will be disabled from that time:
• If this register is read out.
• If writing to this register is performed by the procedure other than the above procedure.
7906 Group User’s Manual Rev.2.0
20-32
RENESAS [ RENESAS TECHNOLOGY CORP ]
