IBM 5150 PC Technical Reference (6025005, August, 1981) (PDF)

Table 10. Connector Pin Assignment and Descriptions
ofInterface Signals
Signal Return
Pin No. Pin No.
1 19
2 20
3 21
4 22
5 23
6 24
7 25
8 26
9 27
10 28
11 29
Signal
STROBE
DATA 1
DATA 2
DATA 3
DATA 4
DATA 5
DATA 6
DATA 7
DATA 8
ACKNLG
BUSY
Direction
In
In
In
In
In
In
In
In
In
Out
Out
Description
STROBE pulse to read
data in. Pulse width
must be more than
O.5J.1S at receiving
terminal.
The signal level is
normally "HIGH";
read·in of data is per·
formed at the "LOW"
level of this signal.
These signals represent
information of the
1st to 8th bits of
parallel data respectively.
Each signal is
at "HIGH" level when
data is logical "1" and
"LOW" when logical
"0".
Approx .. 5J.1S pulse.
"LOW" indicates that
data has been received
and that the printer
is ready to accept
other data.
A "HIGH" signal
indicates that the
printer cannot receive
data. The signal
becomes "High" in
the following cases:
1. During data entry
2. During printing
operation
3. In OFF·LlNE state
4. During printer error
status.
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