PacComm TINY-2 - Serial Data Signal Definitions

COMPUTER
INTERFACING
Serial
Data
Signal
Definitions
Serial
Port
Operation
At
TTL
Levels
The
TINY-2/MIGRO-2
packet
controller
is
designed
to
operate
with
computers
which
have
a
TTL
level
serial
port
without
requiring
the
use
of
an
RS-232C
adapter.
This
includes
such
popular
computers
as
the
Commodore
VIC-20,
C-64,
and
C-128.
TTL
signals
are
routed
through
an8
pin
connector
on
the
rear
panel.
TTL
signal
levels
must
be
greater
than
+2.4
volts
in
one
state
and
less
than
+.4
volt
in
the
other
state.
Use
caution
in
connecting
the
TTL
cable
to
insure
that
pin
one
of
the
cable
is
attached
to
pin
one
of
the
connector.
Pin
one
is
clearly
marked
on
the
rear
panel
of
the
controller.
Pin
one
of
the
cable
connector
is
marked
with
a
red
stripe.
Be
sure
to
observe
this
marking
both
in
constructing
and
attaching
the
cable.
TTL
serial
port
signals
used
by
the
TINY-2/MICRO-2
controller.
P3
Signal
Name
Description
1
Receive
Data
Serial
data
to
computer
from
the
TINY-2/MIGRO-2.
2
Garrier
Detect
Goes
high
when
connection
exists.
3
Frame
Ground
Common
ground
for
case
and
data
lines.
4
Clearto
send
Computer
signal
clearing
controller
to
send
data.
5
Transmit
Data
Seriat
data
to
the
TINY-2/MICRO-2
from
computer.
6
SignalGround
Common
ground
for
both
data
lines
and
case.
7
Requesttosend
Controller
signal
to
computer
when
data
is
ready.
8
NoConnection
:
Serial
Data
Signal
Definitions
This
section
describes
the
pins
used
on
the
packet
controller's
serial
port
connectors.
Since
the
pins
are
defined
with
respect
to
the
Data
Terminal
Equipment
(DTE)
(computer)
end
of
the
circuit,
and
the
packet
controller
is
wired
as
Data
Communications
Equipment
(DCE)
(modem),
some
standard
pin
names
appear
to
be
the
reverse
of
the
packet
controller
function.
Acomplete
RS-232
signal
table
appears
in
the
Appendices.
Serial
Port
Pin
Functions
+
Frame
Ground
(FG)
is
provided
for
attachmentto
the
chassis
of
the
packet
controller
and
the
chassis
of
the
attached
computer
terminal.
This
is
common
to
the
signal
ground
on
the
TINY-2/MICRO-2.
+
Transmit
Data
(TXD)
is
an
input
line
to
the
packet
controller
on
which
the
attached
computer
terminal
device
sends
data.
+
Receive
Data
(RXD)
is
an
output
line
from
the
TINY-2/MICRO-2
on
which
it
sends
data
to
the
attached
computer
terminal
device.
*
Request
to
Send
(RTS)
is
an
input
to
the
packet
controller
signaling
that
the
attached
computer
terminal
device
is
ready
to
accept
data
from
the
TINY-2/MICRO-2.
This
line
is
used
for
hardware
flow
control.
+
Clear
To
Send
(CTS)
is
an_output
from
the
packet
controller
signaling
the
attached
computer
terminal
device
to
send
data
to
the
TINY-2/MICRO-2.
This
line
is
used
for
hardware
flow
control.
eee
4
TINY-2/MICRO-2
Technical
Ref.,
2
Ed
©
1989,
PacComm,
Inc.