SECTION 5.
INTERFACE SPECIFICATIONS
INTERFACE TYPES
The parallel interface for the PTR3E printer is a high speed, bi-directional interface
that conforms to the IEEE1284 specification (ECP mode on some computers). The
interface is also compatible with the older Centronics parallel interface standard. If it
does not detect the correct IEEE1284 signals I the interface connection, it will
automatically operate in the standard Centronics mode which is much slower. To use
the IEEE1284 parallel interface to its fullest capability requires that the host also have
an IEEE1284 compatible interface and that the two be connected with a cable that
meets the IEEE1284 specification. If either of these two are not present, the data rate
is severely compromised.
In order to provide flexibility in communicating with a variety of host computer
systems all “e” printers use a Plug-In Interface Module. The IEEE1284 Interface
module is shipped with the printer unless another interface type is specified at the time
of the order. A serial interface at a high speed to 57.6k bps is also available.
The Parallel interface will probably be the most useful in communicating with IBM
purchase and compatibles. The RS232C Serial interface allows connectivity to a
number of other hosts.
WARNING: Never connect or disconnect interface cables (or use a switch box) with
power applied to either the host or the printer. This may cause damage to the
interface circuitry in the printer/host and is not covered by warranty.
IEEE1284 PARALLEL INTERFACE
The parallel interface for the PTR3E printer is a Plug-In Interface Module that can be
installed by the user. It conforms to the IEEE1284 specification. It will automatically
detect the IEEE1284 signals and operate in the high speed mode. If it does not detect the
IEEE1284 signals, it will operate in the standard Centronics mode, which is significantly
slower.
For this reason, an interface cable and host interface conforming to the IEEE1284
specification must be present to fully utilize the speed capabilities.
This interface also
operates bi-directionally and can report the status of the printer back to the host.
ELECTRICAL SPECIFICATIONS
Printer Connector
AMP 57-40360 (DDK) or equivalent
Cable Connector
AMP 57-30360 (DDK) or equivalent
Cable
IEEE1284 Parallel, 10 ft. (3 m) or less
Signal Level
High = +2.4V to +5.0V
Low = 0V to -0.4V
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