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A-10
Technical Specifications
nFault/nDataAvail/nPeriphRequest
Compatibility mode: Low signal indicates that an error occurred.
negotiation phase: This signal is set high in order to authorize 1284
compatibility. In nibble mode, after the host sets
HostBusy (nAutoFd) high, this signal is set low
in order to indicate that the transmission data is
ready.
reverse data transfer phase: This signal is set low in order to indicate to a
nibble mode host that the transmission data is
ready. Afterwards, this signal serves as nibble
data bit 0 and then 4.
reverse final phase: Indicates whether or not the data is valid.
ECP mode: This signal is set low to request communications
with the host. Valid in both forward and reverse
direction.
nSelectIn/IEEE1284active
Compatibility mode: Always low.
negotiation phase: This signal is set high at the same time that
HostBusy is low in order to request 1284 mode.
reverse data transfer phase: This signal is set high to indicate that the bus
direction is from the printer to the host. This
signal is set low to terminate 1284 mode, setting
the bus direction from the host to the printer.
reverse idle phase: Same as reverse data transfer phase.
ECP mode: Always high. This signal is set low to terminate
ECP mode and return to compatibility mode.
GND
Twisted pair return signal.
CG
Connected to the printer chassis. This signal and GND are connected.
+5V
Pull up to + 5 V with 1 k
Ω
.