Anadex DP-9000 Operator's Manual page 31

2~9.2
SERIAL BIT, SERIAL CHARACTER - RS-232-C: This inter-
face system conforms to EIA standard RS-232-C. In utilizing.
this convention, the user must recognize that the printer is
the DTE (Data Terminal Equipment) and configure the inter-
connection between the DTE and the DCE (Data Communications
Equipment), which may be a modem or Data terminal (CRT) or a
computer or other source. The EIA RS-232-C communications
standard is a two-way communications standard, and therefore
a signal which is defined as an output at one end may be an input
at the other end. For example: TD (TRANSMIT DATA), which is
assigned to pin 2 of the connector, is the data output line of
the DCE, but is RD (RECEIVE DATA) at the DTE and is assigned
to pin 3 of the DTE connector. Therefore, unless provision is
available in the data source interface to switch these signal
lines, the signal lines may require cross-connection from pin
3 to pin 2 in the cable. This principle applies to all signals
in the RS-232-C interface.
NOTE
Those users who are not thoroughly knowledge-
able in RS-232-C serial interface communica-
tion should refer to troubleshooting in
Section IV for guidance in establishing com-
munication.
The serial connector for both RS-232-C and current loop inter-
face is the 25 pin connector at the rear left of the printer.
Figure 2-7 shows the pin connections and internal strapping
for the serial connector J-2, and Figure 2-8 shows the timing
relationship of the data and status signals. The following
paragraphs describe each of the input/output signals:
EIA DATA-IN
INPUT
This is the asynchronous input data line.
Data format is established by switch con-
figuration by the operator. The format is
one start bit, 7 or 8 data bit word,
0
to
1 parity bit, and I or 2 stop bits. Bit
length is determined by the Baud rate and
is nominally:
I sec.
t
Baud Rate
Signal levels for this interface are based
upon conventional SPACE and MARK levels.
The voltage level for a SPACE is
+
3 Vdc to
+
25 Vdc, and voltage level for a MARK is
- 3 Vdc to - 25 Vdc.
2-17