CHAPTER 6 STBC
Preliminary User’s Manual A14874EJ3V0UM
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Remarks 5.
The following shows the operation when a non-maskable interrupt or maskable interrupt is
requested while a NOP instruction is being executed.
•
If a non-maskable or maskable interrupt is requested before SWSTOPRQ becomes active, the
interrupt servicing is immediately executed.
•
If a non-maskable or maskable interrupt is requested after SWSTOPRQ became active, the
STOP mode is canceled by the requested interrupt after the STOP mode is entered, in the same
way as cancellation by a normal interrupt.
6.2.2 Command register (PRCMD)
The command register (PRCMD) is used to set protection for write operations to the PSC register so that the
application system is not halted unexpectedly due to erroneous program execution.
Only the first write operation to the PSC register is valid after a registration code (arbitrary 8-bit data) is written to
the PRCMD register. Since the register value can be rewritten only by a predetermined procedure, illegal write
operations to the PSC register are rejected.
Data can be written in the PRCMD register only in 8-bit units. During reading, the value is undefined.
Caution Do not set the PRCMD register by transferring data using the DMAC. To set this register, always
use a store instruction (ST or SST).
Figure 6-3. Command Register (PRCMD)
7
6
5
4
3
2
1
0
PRCMD
REG7
REG6
REG5
REG4
REG3
REG2
REG1
REG0
Address
FFFFF1FCH
After reset
Undefined
Bit position
Bit name
Function
7 to 0
REG7 to
REG0
This is the registration code (arbitrary 8-bit data) used when write accessing the PSC register.