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CHAPTER 7 SYSTEM REGISTER (SYSREG)
45
7.3 WINDOW REGISTER (WR)
7.3.1 Window Register Configuration
Figure 7-5 shows the configuration of the window register.
As shown in Figure 7-5, the window register (WR) consists of four bits allocated at address 78H of the system
register. The contents of the window register is undefined after a system reset. However, when RESET input is
used to release the system from HALT or STOP mode, the previous state of the window register is maintained.
Figure 7-5. Window Register Configuration
7.3.2 Window Register Functions
The window register is used to transfer data to and from the register file (RF).
Data is transferred to and from the register file using the instructions PEEK WR, rf and POKE rf, WR. For details,
refer to
9.2.3 Register File Manipulation Instructions
.
78H
Window register
WR
Not defined
Address
Name
Bit
Symbol
Data
Initial value when reset
b
3
b
2
b
1
b
0
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