Philips Semiconductors
Product specification
I
2
C-bus controller
5
PINNING
SYMBOL
CLK
SDA or
SDA OUT
SCL or SCL IN
IACK or
SDA IN
INT or
SCL OUT
A0
PIN
1
2
3
4
I/O
I
I/O
I/O
I
DESCRIPTION
clock input from microcontroller clock generator (internal pull-up)
PCF8584
I
2
C-bus serial data input/output (open-drain). Serial data output in long-distance
mode.
I
2
C-serial clock input/output (open-drain). Serial clock input in long-distance mode.
Interrupt acknowledge input (internal pull-up); when this signal is asserted the
interrupt vector in register S3 will be available at the bus Port if the ENI flag is set.
Serial data input in long-distance mode.
Interrupt output (open-drain); this signal is enabled by the ENI flag in register S1.
It is asserted when the PIN flag is reset. (PIN is reset after 1 byte is transmitted or
received over the I
2
C-bus). Serial clock output in long-distance mode.
Register select input (internal pull-up); this input selects between the control/status
register and the other registers. Logic 1 selects register S1, logic 0 selects one of
the other registers depending on bits loaded in ESO, ES1 and ES2 of register S1.
bidirectional 8-bit bus Port 0
bidirectional 8-bit bus Port 1
bidirectional 8-bit bus Port 2
ground
bidirectional 8-bit bus Port 3
bidirectional 8-bit bus Port 4
bidirectional 8-bit bus Port 5
bidirectional 8-bit bus Port 6
bidirectional 8-bit bus Port 7
RD is the read control input for MAB8049, MAB8051 or Z80-types. DTACK is the
data transfer control output for 68000-types (open-drain).
chip select input (internal pull-up)
WR is the write control input for MAB8048, MAB8051, or Z80-types
(internal pull-up). R/W control input for 68000-types.
Reset input (open-drain); this input forces the I
2
C-bus controller into a predefined
state; all flags are reset, except PIN, which is set. Also functions as strobe output.
supply voltage
5
O
6
I
DB0
DB1
DB2
V
SS
DB3
DB4
DB5
DB6
DB7
RD (DTACK)
CS
WR (R/W)
RESET/
STROBE
V
DD
7
8
9
10
11
12
13
14
15
16
17
18
19
20
I/O
I/O
I/O
−
I/O
I/O
I/O
I/O
I/O
I/(O)
I
I
I/O
−
1997 Oct 21
5
PHILIPS [ NXP SEMICONDUCTORS ]
