HP 4 FAMILY - Manual (Page 128)

IEEE-P1284. This bi-directional enhanced capability
port (ECP) allows most printer features to be monitored
and controlled through Microsoft Windows or a DOS
remote control panel shipped with the product. In
previous HP printers, PJL provided some job-level status
and control, but PJL is embedded in the data stream,
synchronous with the printer description data. With the
implementation if MLC (Multiple Logical Channels) on
the ECP and MIO 6.0, the printer can be controlled and
monitored on a separate channel, asynchronous to the
data stream. PJL still provides control that must be
synchronous with the data stream.
Energy Star. The printer lowers its power consumption
if it has not been used for 15 minutes.
Out-of-Ink Sensing. An LED on the control panel
lights when a pen runs out of ink.
MIO. Modular I/O interface with auto-sensing I/O
configuration.
JetDirect. Optional network cards: Novell, TCP-IP,
LocalTalk, EtherTalk, and third party.
PostScript. A SIMM upgrade is available.
Optional Media Source. An optional sheet feeder tray
is available.
Media Detection. Automatic detection of media size
and media type (transparency).
2-92 Printer-Specific Differences