W77C32F-40 Nuvoton Technology Corporation of America, W77C32F-40 Datasheet - Page 12

• Manufacturer Part Number: W77C32F-40
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of W77C32F-40

• Lead Free Status / Rohs Status: Supplier Unconfirmed

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
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
This is the low byte of the standard 8052 16-bit data pointer.
Data Pointer High
This is the high byte of the standard 8052 16-bit data pointer.
Data Pointer Low1
This is the low byte of the new additional 16-bit data pointer that has been added to the W77C32. The
user can switch between DPL, DPH and DPL1, DPH1 simply by setting register DPS = 1. The
instructions that use DPTR will now access DPL1 and DPH1 in place of DPL and DPH. If they are not
required they can be used as conventional register locations by the user.
Data Pointer High1
Bit:
Bit:
Mnemonic: SP
Mnemonic: DPL
Mnemonic: DPH
Mnemonic: DPL1
Mnemonic: DPH1
DPL1.7
DPH1.7
Bit:
7
7
Bit:
Bit:
DPH.7
DPL1.6
DPH1.6
DPL.7
7
SP.7
6
6
7
7
DPH.6
DPL1.5
DPL.6
DPH1.5
SP.6
6
6
6
5
5
DPH.5
DPL.5
DPL1.4
SP.5
- 12 -
5
DPH1.4
5
5
4
4
DPH.4
DPL.4
SP.4
DPL1.3
4
4
4
DPH1.3
3
3
DPL.3
DPH.3
SP.3
3
3
3
DPL1.2
W77C32/W77C032
DPH1.2
2
Address: 81h
Address: 82h
Address: 83h
Address: 84h
Address: 85h
2
DPL.2
SP.2
DPH.2
2
2
2
DPL1.1
DPH1.1
1
DPL.1
SP.1
1
DPH.1
1
1
1
DPL1.0
DPH1.0
0
DPL.0
SP.0
DPH.0
0
0
0
0