MS51
Dec. 17, 2019
Page
39
of 316
Rev 1.01
M
S51
SE
RIES
TE
CHNICA
L REF
ERE
N
CE MA
NU
A
L
Pn
– Port n (Bit-addressable)
Regiser
Address
Reset Value
P0
80H, all pages, bit addressable
1111_1111 b
P1
90H, all pages, bit addressable
1111_1111 b
P2
A0H, all pages, bit addressable
0000_0001 b
P3
B0H, all pages, bit addressable
0000_0001 b
7
6
5
4
3
2
1
0
Pn.7
Pn.6
Pn.5
Pn.4
Pn.3
Pn.2
Pn.1
Pn.0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
