Appendix Description of the physical interface
T5023/5023+ - Programming Guide 381
PeriphAck/Busy (Printer driven)
Compatibility Mode: Driven ’high’ to indicate that the printer is not
ready to receive data.
ECP Mode: The printer uses this signal for flow control in
the forward direction. PeriphAck also provides a
ninth data bit used to determine whether
command or data information is present on the
data signals in the reverse direction.
Epson ANSI: Busy = 0: STOP status and printer ready
Busy = 1: STOPstatus , Error or printer not
ready
nAckReverse/PError (Printer driven)
Compatibility Mode: Driven ’high’ to indicate that the printer has
encountered an error in its paper path.
ECP Mode: The printer drives this signal ’low’ to
acknowledge nReverseRequest. The host relies
upon nAckReverse to determine when it is
permitted to drive the data signals.
Epson ANSI: The signal nFault is not activ at PError but in the
global printer status ’ERROR’ it is activ.
Centronics = ECP PError is set to status that means PError is activ
if the special printer message NO_PAPER is
send to the system.
Centronics = printer PError is set to error that means PError only set
activ if data is send to the printer without paper
inside.