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Chapter 3
CPU Functions
User’s Manual U16580EE3V1UD00
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Processor command register (PRCMD)
The PRCMD register is an 8-bit register used to prevent data from being written to registers that
may have a large influence on the system, possibly causing the application system to
unexpectedly stop. Only the first write operation to a specific register following the execution of a
write operation to the PRCMD register, is valid.
As a result, register values can be overwritten only using a preset sequence, preventing invalid
write operations.
PRCMD register must be written with store instruction execution by CPU only (not with DMA
transfer). If an illegal store operation to a command or specific register takes place, it is reported
by the PRERR flag of the system status register (PHS).
This register can be written in 8-bit units only. Undefined data is read from this register.
Figure 3-25:
Processor Command Register (PRCMD)
After reset:
Undefined
W
Address:
FFFFF1FCH
7
6
5
4
3
2
1
0
PRCMD
REG7
REG6
REG5
REG4
REG3
REG2
REG1
REG0
Summary of Contents for MuPD70F3187
Page 6: ...6 Preface User s Manual U16580EE3V1UD00 ...
Page 16: ...16 User s Manual U16580EE3V1UD00 ...
Page 28: ...28 User s Manual U16580EE3V1UD00 ...
Page 32: ...32 User s Manual U16580EE3V1UD00 ...
Page 84: ...84 Chapter 2 Pin Functions User s Manual U16580EE3V1UD00 MEMO ...
Page 144: ...144 Chapter 3 CPU Functions User s Manual U16580EE3V1UD00 MEMO ...
Page 312: ...312 Chapter 9 16 Bit Timer Event Counter P User s Manual U16580EE3V1UD00 MEMO ...
Page 534: ...534 Chapter 11 16 bit Timer Event Counter T User s Manual U16580EE3V1UD00 ...
Page 969: ...969 Chapter 20 Port Functions User s Manual U16580EE3V1UD00 MEMO ...
Page 970: ...970 Chapter 20 Port Functions User s Manual U16580EE3V1UD00 ...
Page 976: ...976 Chapter 22 Internal RAM Parity Check Function User s Manual U16580EE3V1UD00 MEMO ...
Page 984: ...984 Chapter 23 On Chip Debug Function OCD User s Manual U16580EE3V1UD00 MEMO ...
Page 1006: ...1006 Chapter 24 Flash Memory User s Manual U16580EE3V1UD00 MEMO ...
Page 1036: ...1036 Chapter 27 Recommended Soldering Conditions User s Manual U16580EE3V1UD00 MEMO ...
Page 1046: ...1046 Appendix A Index User s Manual U16580EE3V1UD00 MEMO ...
Page 1052: ...1052 User s Manual U16580EE3V1UD00 ...
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