MS51
Dec. 17, 2019
Page
306
of 316
Rev 1.01
M
S51
SE
RIES
TE
CHNICA
L REF
ERE
N
CE MA
NU
A
L
7
6
5
4
3
2
1
0
DPH[7:0]
R/W
Bit
Name
Description
7:0
DPH[7:0]
Data pointer high byte
This is the high byte of 16-bit data pointer. DPH combined with DPL serve as a 16-bit data pointer
DPTR to access indirect addressed RAM or Program Memory. DPS (AUXR1.0) bit decides which
data pointer, DPTR or DPTR1, is activated.
AUXR1
– Auxiliary Register 1
Regiser
Address
Reset Value
AUXR1
A2H, all pages
POR 0000_0000b,
Software 1U00_0000b
nRESET pin U100_0000b
Others UUU0_0000b
7
6
5
4
3
2
1
0
SWRF
RSTPINF
HardF
SLOW
GF2
UART0PX
0
DPS
R/W
R/W
R/W
R/W
R/W
R/W
R
R/W
Bit
Name
Description
3
GF2
General purpose flag 2
The general purpose flag that can be set or cleared by the user via software.
0
DPS
Data pointer select
0 = Data pointer 0 (DPTR) is active by default.
1 = Data pointer 1 (DPTR1) is active.
After DPS switches the activated data pointer, the previous inactivated data pointer remains its
original value unchanged.