PacComm TINY-2 - Page 126

COMPUTER
INTERFACING
Serial
Data
Signal
Definitions
»
Data
Set
Ready
(DSR)
is
an
output
from
the
packet
controller
telling
the
attached
computer
terminal
device
that
the
packet
controller
is
operational.
On
the
TINY-2/MICRO-2
this
pin
is
tied
high
(ready).
+
Signal
Ground
(SG)
is
the
common,
or
return,
path
for
ail
signals
between
the
TINY-2/MICRO-2
and
the
attached
computer
terminal
device.
It
is
common
with
the
frame
ground.
»
Data
Carrier
Detect
(DCD)
is
an
output
from
the
packet
controller.
DCD
reflects
the
status
of
the
CON
LED:
It
is
high
when
a
packet
connection
exists
and
it
is
low
when
no
connection
exists.
This
signal
is
useful
when
the
packet
controller
is
used
with
telephone
style
and
BBS
software,
since
the
connect
signal,
like
a
modem
carrier
on
the
telephone,
indicates
the
presence
of
a
user.
»
Data
Terminal
Ready
(DTR)
is
an
input
to
the
TINY-2/MICRO-2
signaling
that
the
attached
computer
terminal
device
is
ready
to
accept
data
from
the
packet
controlier.
Not
used
on
the
TINY-2/MICRO-2.
The
table
below
provides
a
cross
reference
to
the
pinouts
of
the
industry
standard
25
pin
connector
as
used
on
many
computers
and
terminals,
the
TNC-2
and
PacComm
TNC-200,
and
relates
them
to
the
newer
9
pin
connectors
used
on
many
modern
computers
and
the
TINY-2/MICRO-2.
Note
that
connecting
a
DTE
device
to
a
DCE
device
using
either
25
pin
connectors
or
9
pin
connectors
at
both
ends
of
the
cable
provides
a
’straight
through’
wiring
of
pin
numbers,
i.e.
connect
column
1
to
column
4
OR
connect
column
2
to
column
3.
However,
when
a
25
pin
connector
and
9
pin
connector
are
used
on
the
same
cable,
i.e.
column
1
to
column
3,
several
pairs
of
signal
lines
must
be
crossed.
TINY-2/MICROPOWER-2
RS-232
Serial
Port
Signal
Cross
Reference
1
2
3
4
Conventional
Conventional
IBM
AT
TINY/MICRO
TNC-2(00)
RS-232-
RS-232DTE
RS-232DTE
RS-232DCE
RS-232
DC
DB-25
DE-9P
DE-9P
OB-25S
Definition
Pin
Nr.
Pin
Nr.
Pin
Nr.
Pin
Nr.
FG
1
shell
5
1
TXD
2
3
3
2
RXD
3
2
2
3
RTS
4
7
7
ne
cTs
5
8
8
5
DSR
6
6
6
6
SG
7
5
5
7
DCD
8
1
1?
8?
Test
9
V+
+
+12V
Test
10
V-
-
-12V
DTR
20
4
nce
20
RI
22
9
9°
(23)
.
,
This
line
goes
high
when
a
connection
exists
RFDCD
(Also
used
for
multinode
NET/ROM
and
ROSE)
ene
nn
TINY-2/MICRO-2
Technical
Ref.,
2
Ed
©
1989,
PacComm,
Inc.
5