HP 2500C Series - Manual (Page 20)

Product Information 1-12
Specifications
IEEE 1284 Pinout Information
Any standard IEEE 1284 compliant printer cable will work with the printer. The
customer can order the HP IEEE 124 Compliant Parallel Interface Cable C2950A (2
meters) or C2951A (3 meters). See Ordering Parts in Chapter 12 for ordering
information.
P IN N UMBER P IN ID D ESCRIPTION
1 HostClk Used in a closed-loop handshake with PeriphAck to transfer data or address
information from the host to the peripheral device.
2 - 9 AD1 - AD8 Host to peripheral device or peripheral device to host address or data. Data 1 is
the least significant bit (bit 0).
10 PeriphClk Used in a closed-loop handshake with HostAck (nAutoFd) to transfer data from
the peripheral device to host.
11 PeriphAck The peripheral uses this signal for flow control in the forward direction.
PheriphAck also provides a ninth data bit to determine whether command or
data information is present on the data signals in the reverse direction.
12 nAckReverse The peripheral drives this signal low to acknowledge nReverseRequest. The
host relies upon nAckReverse to determine when it is permitted to drive the
data signals.
13 Xflag This is used by the peripheral device to reply to the requested extensibility byte
during the negotiation phase.
14 HostAck The host drives this signal for flow control in the reverse direction. It is used in
an interlocked handshake with PeriphClk. Host Ack also provides a ninth data
bit used to determine whether command or data information is present on the
data signals in the forward direction.
16 Logic Ground Logic board ground.
17 Chassis Ground Chassis Ground.
18 Peripheral Logic High This signal is used to provide +5V high logic.
19-30 Ground These pins are tied to signal ground
31 nReverseRequest This signal is driven low to place the channel in the reverse direction. While in
ECP mode, the peripheral is only allowed to driver the bi-directional data
signals when nReverseRequest is low and 1284 Active is high.