W925EP01 Datasheet, PDF (25/108 Pages) Winbond – 8-BIT CID MICROCONTROLLER

W925EP01/ W925EP01FG
When “MOVC A, @A+DPTR” is executed to read the external ROM data or “MOVX dest, src”
is executed to access the external data RAM, the P7 pins can be treated as data bus of
external data storages.
P7 inputs the data <7:0> of the external ROM. Or, P7 inputs/outputs the data <7:0> of the
external data RAM.
PORT 6
(initial=FFH)
Bit:
7
6
5
4
3
2
1
0
P6.7 P6.6 P6.5 P6.4 P6.3 P6.2 P6.1 P6.0
Mnemonic: P6
Address: A5h
P6.7-0: Port 6 is an I/O port with internal pull-high resistor. P6 can be selected as input or output
mode by the P6IO register, at initial reset, P6IO is set to 1, P6 is used as input mode. When
P6IO is set to 0, P6 is used as CMOS output mode.
The special function of P6 is as address bus of external program ROM or external data RAM.
The program memory on the standard 8052 can only be addressed to 64KB long. W925EP01
can extend to two 64KB program ROM banks; there are on-chip APROM bank and external
program ROM bank. When PG=1, the P6 pins can be treated as address high bus of external
program ROM. When PG=0, the P6 pins can be treated as normal I/O.
When “MOVC A, @A+DPTR” is executed to read the external ROM data or “MOVX dest, src”
is executed to access the external data RAM, the P6 pins can be treated as address high bus
of external data storages.
PORT 4
(initial=FFH)
Bit:
7
P4.7
Mnemonic: P4
6
P4.6
5
P4.5
4
P4.4
3
2
1
P4.3 P4.2 P4.1
Address: A6h
0
P4.0
P4.7-0: Port 4 is an I/O port with internal pull-high resistor. P4 can be selected as input or output
mode by the P4IO register. At initial reset, P4IO is set to 1; P4 is used as input mode. When
P4IO is set to 0, P4 is used as CMOS output mode. Special function of P4 is described below.
P4.7-5
P4.4
P4.3
P4.2
P4.1
P4.0
I/O
VPOS
I/O
VNEG
SDATA1
SCLK1
Normal I/O
Positive input of the comparator
Normal I/O
Negative input of the comparator
Serial port1 data I/O
Serial port1 clock I/O with Smith trigger in input path
- 25 -
Publication Release Date: Apr. 10, 2006
Revision A2