Instruction manual

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Chapter 6 Printer Interface
DC Power
The power supply board contains two DC power supply systems for the
printer. The first is a +5 V bus for logic. The second consists of +48 V and
+8.5 V buses for the hammer bank and all motors.
The +5 V supply has an isolated return line that connects to the +48 V return
at the printer load. Both returns are tied together in a one-point ground. The
+5 V power supply has its own inverter, separate from the +48 V and +8.5 V
outputs.
There is an opto-isolated input on the power supply that will shut down and
latch off the +48 V and +8.5 V supplies unless it is pulled up to +5V with a 1K
Ω resistor. This resistor is mounted on the controller board and may be pulled
down or disconnected by software or internal cable interlocks. The
+5 V output will remain stable for reporting and latching the fault condition.
The return for this signal is the +5 V return. In addition, this shutdown circuit
discharges and latches the +48 V down to a level lower than +15 V in less
than 200 milliseconds and requires recycling of the circuit breaker (On/Off
switch) to reset the latch.
Loss of +48 V is seen by the EC and reported as a fault.
Printer Interface
The printer interface is the point where the data cable from the host computer
plugs into the printer. The printer interface processes all signals and data to
and from the host computer.
The printer supports a number of standard and optional interfaces to the host:
• Centronics parallel (standard)
• IEEE 1284 parallel (standard)
• EIA®-232-E serial (standard)
• EIA-422-B serial (standard)
• Dataproducts Long Lines parallel (optional)
• Coaxial/twinaxial Expansion-CT (optional)
• PrintNet 10Base2 or 10Base-T Ethernet adapter (optional)
Selection of the interface is controlled by configuration menus accessed at the
control panel. It is possible to physically connect more than one interface, but
only one interface at a time can be used electrically.