W78E58B Winbond, W78E58B Datasheet - Page 7

• Manufacturer Part Number: W78E58B
• Description: 8 BIT MICROCONTROLLER
• Manufacturer: Winbond

Continued
Notes:
1.The SFRs marked with a plus sign(+) are both byte- and bit-addressable.
2. The text of SFR with bold type characters are extension function registers.
Port 4
Port 4, address D8H, is a 4-bit multipurpose programmable I/O port. Each bit can be configured
individually by software. The Port 4 has four different operation modes.
Mode 0: P4.0
Mode 1: P4.0
Mode 2: P4.0
Mode 3: P4.0
When Port 4 is configured with the feature of chip-select signals, the chip-select signal address range
depends on the contents of the SFR P4xAH, P4xAL, P4CONA and P4CONB. The registers P4xAH
and P4xAL contain the 16-bit base address of P4.x. The registers P4CONA and P4CONB contain the
control bits to configure the Port 4 operation mode.
Two additional external interrupts, INT2 and INT3 , whose functions are similar to those of external
interrupt 0 and 1 in the standard 80C52. The functions/status of these interrupts are determined/shown
by the bits in the XICON (External Interrupt Control) register. The XICON register is bit-addressable
but is not a standard register in the standard 80C52. Its address is at 0C0H. To set/clear bits in the
XICON register, one can use the "SETB ( CLR ) bit" instruction. For example, "SETB 0C2H" sets the
EX2 bit of XICON.
INT2
A8
A0
98
90
88
80
/
I
00000000
11111111
00000000
11111111
00000000
11111111
NT3
+SCON
+TCON
external interrupt INT3 and NT2
addresses. These signals can be used as chip-select signals for external peripherals.
addresses. These signals can be used as chip-select signals for external peripherals.
specified addresses. These signals can be used as chip-select signals for external
peripherals.
+P2
+P1
+P0
+IE
P4.3 is a bi-directional I/O port which is same as port 1. P4.2 and P4.3 also serve as
P4.3 are read strobe signals that are synchronized with RD signal at specified
P4.3 are write strobe signals that are synchronized with WR signal at specified
P4.3 are read/write strobe signals that are synchronized with RD or WR signal at
00000000
00000111
xxxxxxxx
TMOD
SBUF
SP
00000000
00000000
DPL
TL0
I
00000000
00000000
if enabled.
DPH
TL1
- 7 -
00000000
00000000
00000000
00000000
P42AL
P41AL
P40AL
TH0
Publication Release Date: March 18, 2002
00000000
00000000
00000000
00000000
P42AH
P41AH
P40AH
TH1
0000xx00
P2ECON
W78E58B
00110000
PCON
Revision A3
AF
A7
9F
8F
97
87