141
Chapter 3
CPU Functions
User’s Manual U16580EE3V1UD00
(3)
System status register (PHS)
The PHS register is an 8-bit register to which the PRERR flag showing the generation of
protection errors is assigned.
If a write operation to a specific register has not been executed in the correct sequence including
the access to the command register (PRCMD), the write operation to the intended register is not
executed, a protection error is generated and the PRERR flag is set to 1. The value of this register
becomes “00H” by RESET input.
This register can be read/written in 8-bit and 1-bit units.
Figure 3-26:
System Status Register Format PHS
The PRERR flag operates under the following conditions.
(a) Setting condition (PRERR flag = 1)
•
When a write operation is not performed on the PRCMD register and an operation to write a
specific register is performed (when <4> in the example
3.4.8
(1) Setting data to specific
registers
is executed without <3>).
•
If a write operation (including a bit manipulation instruction) is performed on an on-chip
peripheral I/O register other than a specific register after a write operation to the PRCMD
register (when <4> in the example
3.4.8
(1) Setting data to specific registers
is not performed
for a specific register).
Remark:
Even if an on-chip peripheral I/O register is read (including a bit manipulation instruction)
between writing the PRCMD register and writing a specific register (such as an access to
the internal RAM), the PRERR flag is not set, and data can be written to the special register.
(b) Clearing condition (PREER flag = 0)
•
When 0 is written to the PRERR flag of the PHS register.
•
When system reset is executed.
Cautions: 1. If 0 is written to the PRERR bit of the PHS register (that is not a specific register)
immediately following write to the PRCMD register, the PRERR bit becomes 0
(write priority).
2. If data is written to the PRCMD register (that is not a specific registers)
immediately following write to the PRCMD register, the PRERR bit becomes 1.
After reset:
00H
R/W
Address:
FFFFF802H
7
6
5
4
3
2
1
0
PHS
0
0
0
0
0
0
0
PRERR
PRERR
Detection of Protection Error
0
Protection error did not occur
1
Protection error occurred
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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