83C166 Siemens Semiconductor Group, 83C166 Datasheet - Page 5

• Manufacturer Part Number: 83C166
• Description: 16-Bit CMOS Single-Chip Microcontroller
• Manufacturer: Siemens Semiconductor Group

Pin Definitions and Functions
Symbol
P4.0 –
P4.1
XTAL1
XTAL2
BUSACT,
EBC1,
EBC0
RSTIN
RSTOUT
Semiconductor Group
Pin
Number
16-17
16
17
20
19
22
23
24
27
28
Input
Output
I/O
O
O
I
O
I
I
I
I
O
Function
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
P4.1
XTAL1:
XTAL2:
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.
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
0
1
1
1
1
ROMless versions must have pin BUSACT tied to ‘0’.
Reset Input with Schmitt-Trigger characteristics. A low level at
this pin for a specified duration while the oscillator is running
resets the SAB 80C166. An internal pullup resistor permits
power-on reset using only a capacitor connected to
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.
A16
A17
Input to the oscillator amplifier and input to the
internal clock generator
Output of the oscillator amplifier circuit.
0
0
1
1
0
0
1
1
4
Least Significant Segment Addr. Line
Most Significant Segment Addr. Line
0
1
0
1
0
1
0
1
8-bit demultiplexed bus
8-bit multiplexed bus
16-bit multiplexed bus
16-bit demultiplexed bus
Single chip mode
Reserved.
Reserved.
Reserved.
SAB 80C166/83C166
V
SS
.