W78ERD2 Datasheet, PDF (10/72 Pages) Winbond – 8-BIT MICROCONTROLLER

W78ERD2
Port 0
Bit:
7
P0.7
6
P0.6
5
P0.5
4
P0.4
3
P0.3
2
P0.2
1
P0.1
0
P0.0
Mnemonic: P0
Address: 80h
Port 0 is an open-drain bi-directional I/O port. This port also provides a multiplexed low order
address/data bus during accesses to external memory.
Stack Pointer
Bit:
7
SP.7
6
SP.6
5
SP.5
4
SP.4
3
SP.3
2
SP.2
1
SP.1
0
SP.0
Mnemonic: SP
Address: 81h
The Stack Pointer stores the Scratchpad RAM address where the stack begins. In other words, it
always points to the top of the stack.
Data Pointer Low
Bit:
7
DPL.7
6
DPL.6
5
DPL.5
4
DPL.4
3
DPL.3
2
DPL.2
1
DPL.1
0
DPL.0
Mnemonic: DPL
Address: 82h
This is the low byte of the standard 8052 16-bit data pointer.
Data Pointer High
Bit:
7
DPH.7
6
DPH.6
5
DPH.5
4
DPH.4
3
DPH.3
2
DPH.2
1
DPH.1
0
DPH.0
Mnemonic: DPH
Address: 83h
This is the high byte of the standard 8052 16-bit data pointer.
Port 4.0 Low Address Comparator
Bit:
7
6
5
4
3
2
1
0
P40AL.7 P40AL.6 P40AL.5 P40AL.4 P40AL.3 P40AL.2 P40AL.1 P40AL.0
Mnemonic: P40AL
Address: 84h
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