W78E054D Datasheet, PDF (20/89 Pages) List of Unclassifed Manufacturers – 8-bit microcontroller

W78E054D/W78E052D Data Sheet
9.1 SFR Detail Bit Descriptions
Port 0
Bit: 7
6
5
4
3
2
1
0
P0.7
P0.6
P0.5
P0.4
P0.3
P0.2
P0.1
P0.0
Mnemonic: P0
Address: 80h
BIT NAME FUNCTION
7-0 P0.[7:0]
Port 0 is an open-drain bi-directional I/O port if SFR P0UPR.0 (bit P0UP) clear to “0”, and
when SFR P0UPR.0 (bit P0UP) set to “1”, Port 0 pins are internally pulled-up.
This port also provides a multiplexed low order address/data bus during accesses to external
memory.
STACK POINTER
Bit: 7
6
5
4
3
2
1
0
SP.7
SP.6
SP.5
SP.4
SP.3
SP.2
SP.1
SP.0
Mnemonic: SP
Address: 81h
BIT NAME FUNCTION
7-0 SP.[7:0] The Stack Pointer stores the Scratch-pad RAM address where the stack begins. In other
words it always points to the top of the stack.
DATA POINTER LOW
Bit: 7
6
5
4
3
2
1
0
DPL.7
DPL.6
DPL.5
DPL.4
DPL.3
DPL.2
DPL.1
DPL.0
Mnemonic: DPL
Address: 82h
BIT NAME
FUNCTION
7-0 DPL.[7:0]
This is the low byte of the standard 8052 16-bit data pointer.
DATA POINTER HIGH
Bit: 7
6
5
4
3
2
DPH.7
DPH.6
DPH.5
DPH.4
DPH.3
DPH.2
Mnemonic: DPH
BIT NAME
FUNCTION
7-0 DPH.[7:0]
This is the high byte of the standard 8052 16-bit data pointer.
1
0
DPH.1
DPH.0
Address: 83h
Port 0 Pull Up Option Register
Bit: 7
6
5
4
3
2
1
0
-
-
-
-
-
-
-
P0UP
Mnemonic: P0UPR
Address: 86h
BIT NAME FUNCTION
0 P0UP 0: Port 0 pins are open-drain.
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Publication Release Date: Jun 9, 2015
Revision A13