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Printronix P7000 H-Series Cartridge Ribbon Printer User Manual

Page 120

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120

Chapter

5

IEEE 1284 Parallel Interface

Printer Clock / Peripheral Clock / Interrup.

Driven by the printer. A signal

from the printer indicating the character or function code has been received
and the printer is ready for the next data transfer.

Printer Busy / Peripheral Acknowledge / nWait.

Driven by the printer.

Indicates the printer cannot receive data. (Data bits 4 and 8 in Nibble mode.)

Acknowledge Data Request / nAcknowledge Reverse.

Driven by the

printer. Indicates the printer is in a fault condition. (Data bits 3 and 7 in Nibble
mode.)

Xflag.

Driven by the printer. A high true level indicating the printer is ready for

data transfer and the printer is on line. (Data bits 2 and 6 in Nibble mode.)

Host Busy / Host Acknowledge / NDStrobe.

Driven by the host. Activates

auto-line feed mode.

Peripheral Logic High.

Driven by the printer. When the line is high, the

printer indicates all of its signals are in a valid state. When the line is low, the
printer indicates its power is off or its signals are in an invalid state.

nReverse Request.

Driven by the host. Resets the interface and forces a

return to Compatibility mode idle phase.

nData Available / nPeripheral Request.

Driven by the printer. Indicates the

printer has encountered an error. (Data bits 1 and 5 in Nibble mode.)

1284 Active / nAStrobe.

Driven by the host. A peripheral device is selected.

Host Logic High

—Driven by the host. When set to high, the host indicates all

of its signals are in a valid state. When set to low, the host indicates its power
is off or its signals are in an invalid state.

nInit

—Resets init interface from the host.