SAB80C166W Datasheet, PDF (4/67 Pages) Siemens Semiconductor Group – C16x-Family of High-Performance CMOS 16-Bit Microcontrollers

SAB 80C166W/83C166W
Pin Definitions and Functions
Pin
Symbol Input (I) Function
No.
Output (O)
16 - 17 P4.0 – I/O
P4.1
16
O
17
O
Port 4 is a 2-bit bidirectional I/O port. It is bit-wise
programmable for input or output via direction bits. For a pin
configured as input, the output driver is put into high-
impedance state.
In case of an external bus configuration, Port 4 can be used to
output the segment address lines:
P4.0
A16
Least Significant Segment Addr. Line
P4.1
A17
Most Significant Segment Addr. Line
20
XTAL1 I
19
XTAL2 O
XTAL1: Input to the oscillator amplifier and input to the
internal clock generator
XTAL2: Output of the oscillator amplifier circuit.
To clock the device from an external source, drive XTAL1,
while leaving XTAL2 unconnected. Minimum and maximum
high/low and rise/fall times specified in the AC Characteristics
must be observed.
22
BUSACT, I
23
EBC1, I
24
EBC0
I
External Bus Configuration selection inputs. These pins are
sampled during reset and select either the single chip mode or
one of the four external bus configurations:
BUSACT EBC1 EBC0 Mode/Bus Configuration
0
0
0
8-bit demultiplexed bus
0
0
1
8-bit multiplexed bus
0
1
0
16-bit muliplexed bus
0
1
1
16-bit demultiplexed bus
1
0
0
Single chip mode
1
0
1
Reserved.
1
1
0
Reserved.
1
1
1
Reserved.
ROMless versions must have pin BUSACT tied to ‘0’.
27
RSTIN I
28
RSTOUT O
Reset Input with Schmitt-Trigger characteristics. A low level
at this pin for a specified duration while the oscillator is running
resets the SAB 80C166W/83C166W. An internal pullup
resistor permits power-on reset using only a capacitor
connected to V_SS.
Internal Reset Indication Output. This pin is set to a low
level when the part is executing either a hardware-, a
software- or a watchdog timer reset. RSTOUT remains low
until the EINIT (end of initialization) instruction is executed.
Semiconductor Group
4