upd70f3402 Renesas Electronics Corporation., upd70f3402 Datasheet - Page 73

• Manufacturer Part Number: upd70f3402
• Description: 32-/16-bit Single-chip Microcontroller With Can Interface
• Manufacturer: Renesas Electronics Corporation.

(3)
Cautions: 1. If 0 is written to the PRERR bit of the SYS register, which is not a special register,
Symbol
SYS
R/W
System status register (SYS)
Status flags that indicate the operation status of the overall system are allocated to this register.
This register can be read or written in 8-bit or 1-bit units.
Operation conditions of PERR flag.
(a) Set condition (PRERR = 1)
• When data is written to a special register without writing anything to the PRCMD register (when
• When data is written to a peripheral I/O register other than a special register (including
(b) Clear condition (PRERR = 0)
• When 0 is written to the PRERR flag of the SYS register
• When the system is reset
<4> is executed without executing <3> in 3.2.3 (1)”Setting data to special registers” on page 71
execution of a bit manipulation instruction) after writing data to the PRCMD register (if <4> in
3.4.8 (1) Setting special register is not the setting of a special register)
R/W
2. If data is written to the PRCMD register, which is not a special register, immedi-
7
0
immediately after a write access to the PRCMD register, the PRERR bit is cleared
to 0 (the write access takes precedence).
ately after a write access to the PRCMD register, the PRERR bit is set to 1.
R/W
PRERR
6
0
0
1
Figure 3-11: System Status Register (SYS) Format
R/W
Protection error did not occur
Protection error occurred
5
0
User’s Manual U16702EE3V2UD00
R/W
Chapter 3 CPU Function
4
0
R/W
Detects protection error
3
0
R/W
2
0
R/W
1
0
PRERR FFFFFB02H
R/W
0
Address
After reset
00H
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