MV20556 Datasheet, PDF (3/30 Pages) Mosel Vitelic, Corp – 8 - Bit MCU Mouse Controller

MOSEL VITELIC INC.
Preliminary
MV20556
Pin Descriptions
20L
PDIP
Pin#
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
20L
SOP
Pin#
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
dice ^Symbol
Active I/O Names
Pad#
4
5
6
7
8
9
10
11
12
13-15
17
18
19
20
21
22
23
24
1
2, 3
RES
RXD/P3.0
TXD/P3.1
XTAL2
XTAL1
#INT0/P3.2
#INT1/P3.3
T0/P3.4
T1/P3.5
VSS
P3.7
P1.0
P1.1
P1.2
P1.3
P1.4
P1.5
P1.6
P1.7
VDD
i Reset
i/o bit 0 of Port 3 & Receive data
i/o bit 1 of Port 3 & Transmit data
i Crystal out
o Crystal in
L/- i/o bit 2 of Port 3 & low true Interrupt 0
L/- i/o bit 3 of Port 3 & low true Interrupt 1
i/o bit 4 of Port 3 & external input to Timer 0
i/o bit 5 of Port 3 & external input to Timer 1
i/o Sink Voltage, Ground
i/o bit 7 of Port 3
i/o bit 0 of Port 1
i/o bit 1 of Port 1
i/o bit 2 of Port 1
i/o bit 3 of Port 1
i/o bit 4 of Port 1
i/o bit 5 of Port 1
i/o bit 6 of Port 1
i/o bit 7 of Port 1
i/o Drive Voltage, +5 Vcc
Signal Descriptions
Vss
Circuit ground potential.
VDD
+5V power supply during operation.
PORT 1
Port 1 is an 8-bit quasi-bidirectional I/O port.
There is a pull-up resistance when operating at either
input or output.
PORT 3
Port 3 is an 7-bit quasi-bidirectinal I/O port. It also
contains the interrupt and timer as well as serial port
pins that are used by various options. The output latch
corresponding to a secondary function must be
programmed to one (1) for that function to operate.
The secondary functions are assigned to the pins of port
3, as follows:
- RXD/data (P3.0). Serial port's transmitter data input
(asynchronous) or data input/output (asynchronous).
- TXD/clock (P3.1). Serial port's transmitter data output
(asynchronous) or data input/output (asynchronous).
- #INT0 (P3.2). Interrupt 0 input or gate control input
for counter 0.
- #INT1 (P3.3). Interrupt 1 input or gate control input
for counter 1.
- T0 (P3.4). Input to counter 0.
- T1 (P3.5). Input to counter 1.
There is a pull-up resistance when operating at either
input or output.
RES
A low to high transition on this pin (V IH1) while the
oscillator is not running resets the MV20556. Holding
high signal (higher than V IH1) on this pin for two
machine cycles (24 clocks) or longer while the oscillator
is running, resets the device.
XTAL 1
Input to the oscillator's high gain amplifier. A crystal or
external source can be used.
XTAL 2
Output from the oscillator's amplifier. Required when a
crystal is used.
Specifications subject to change without notice, contact your sales representatives for the most recent information.
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PID256** 07/97