Parallel

Interface Modes

Parallel Interface Modes

In addition to Centronics parallel communication, your printer’s parallel interface provides IEEE 1284 bidirectional parallel communication, which supports five modes of operation. The printer automatically recognizes and uses the mode dictated by the host.

Byte Mode

Printer-host communication is done in bytes.The byte mode may be used by the host device in a DMA (Direct Memory Access) mode for more efficient operation.

When byte transfer is complete and there is no more data to transmit, the host may do one of the following:

nTerminate and return to the compatibility mode.

nStay in the Host Busy, Data Not Available phase.

nSet Host Busy Low, putting the interface into the idle phase. If there is additional data, the host may do one of the following:

nSet Host Busy Low, indicating that the host can accept additional data.

nStay in the Host Busy, Data Not Available phase.

nTerminate and return to the compatibility mode.

Check your host documentation to see if the host is IEEE 1284 com- patible.

Compatibility Mode

Printer-host communication is done in a manner that ensures com- patibility.

Additional Technical Information

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