Zebra Technologies S-300 manual Parallel Interface, Parallel Cabling Requirements

Appendix

Parallel Interface

The parallel interface provides a means of communication which is typically faster than the previously mentioned serial interface method. In this method, the bits of data which make up a character are sent all at one time over several wires in the cable, one bit per wire.

Data signals are defined as either HIGH or LOW while control signals are either Active or Inactive. This distinction is due to the fact that some Control Signals are active HI while others are active LOW. The voltage levels which represent these conditions are:

Data Signal	Voltage Level
HIGH =	+5 VDC
LOW =	0 VDC

Parallel Cabling Requirements

The required cable must have a standard 36-pin parallel connector on one end, which is plugged into the mating connector located inside the access opening on the left side of the printer. Refer to Figure 1 on page 3. The parallel interface cable would be connected using bail clips, instead of screws, in a similar position as the serial data cable shown in the illustration.

The other end of the parallel interface cable connects to an appropriate point at the host computer.

Data cables must be fully shielded and fitted with metal or metallized connector shells. Shielded cables and connectors are required to prevent radiation and reception of electrical noise.

To minimize electrical noise pickup in the cable:

1.	Keep data cables as short as possible.
2.	Do not bundle the data cables tightly with power cords.
3.	Do not tie the data cables to power wire conduits.
		Appendix

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