W925E240 Datasheet, PDF (13/73 Pages) Winbond – 8-BIT CID MICROCONTROLLER

W925E/C240
STACK POINTER
(initial=07H)
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
SP: 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
(initial=00H)
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
DPL: This is the low byte of the standard 8052 16-bit data pointer.
DATA POINTER HIGH
(initial=00H)
Bit:
7
6
5
4
3
2
1
0
DPH.7 DPH.6 DPH.5 DPH.4 DPH.3 DPH.2 DPH.1 DPH.0
Mnemonic: DPH
Address: 83h
DPH: This is the high byte of the standard 8052 16-bit data pointer.
DATA POINTER LOW1
(initial=00H)
Bit:
7
6
5
4
3
2
1
0
DPL1.7 DPL1.6 DPL1.5 DPL1.4 DPL1.3 DPL1.2 DPL1.1 DPL1.0
DPL1:
Mnemonic: DPL1
Address: 84h
This is the low byte of the new additional 16-bit data pointer. That has been added to the
W925E/C240. The user can switch between DPL, DPH and DPL1, DPH1 simply by setting
register DPS.0 = 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
(initial=00H)
Bit:
7
6
5
4
3
2
1
0
DPH1.7 DPH1.6 DPH1.5 DPH1.4 DPH1.3 DPH1.2 DPH1.1 DPH1.0
Mnemonic: DPH1
Address: 85h
DPH1:
This is the high byte of the new additional 16-bit data pointer. That has been added to the
W925E/C240. 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.
- 13 -
Publication Release Date: July 12, 2005
Revision A10