Registers, Table 20) – Rainbow Electronics AT89C5132 User Manual
Page 22

22
AT8xC5132
4173A–8051–08/02
Registers
Table 20. AUXR1 Register
AUXR1 (S:A2h) – Auxiliary Register 1
Reset Value = XXXX 00X0b
7
6
5
4
3
2
1
0
-
-
ENBOOT
-
GF3
0
-
DPS
Bit
Number
Bit
Mnemonic
Description
7 - 6
-
Reserved
The values read from these Bits are indeterminate. Do not set these Bits.
5
ENBOOT
Enable Boot Flash
Set this bit to map the boot Flash in the code space between at addresses F000h
to FFFFh.
Clear this bit to disable boot Flash.
4
-
Reserved
The values read from this bit is indeterminate. Do not set this bit.
3
GF3
General Flag
This bit is a general-purpose user flag.
2
0
Always Zero
This bit is stuck to logic 0 to allow INC AUXR1 instruction without affecting GF3
flag.
1
-
Reserved for Data Pointer Extension.
0
DPS
Data Pointer Select Bit
Set to select second data pointer: DPTR1.
Clear to select first data pointer: DPTR0.