User's Manual

Functional Overview
10-5
HP DesignJets 500, 510 and 800 Series Printers Service Manual
 The memory bus is also used to control Navata gate array. Navata
is a customized ASIC to control most of the Printer’s sensors (ISS
optical sensors, pinch wheels, digital encoder, etc.), Power
Supply, Scan-Axis Motor driver, Vacuum Fan, Front Panel,
Carriage, etc.
 A 16k serial EEPROM is used to store different line calibration
parameters and the Printer’s life history (number of plots, etc.).
The ISS PCA also contains an EEROM that contains a backup of
all critical parameters from the Main EEROM.
 The Main PCA has an analogue IC which controls two DC
motors (IDS and paper) and one stepper motor (Service Station).
This IC, as well as the IC in the Carriage PCA, is controlled
through the VPR serial interface from the Kayak ASIC at a bus
clock frequency of 1.6MHz.
 From the Main PCA the Interconnect Cable connects to the
Interconnect PCA (located on the right hand side of the Printer)
which then splits into different subsystems: Front Panel, IDS
PCA, Service Station and media loading sensors (pinch, media
sensor and media button).
 Two discrete drivers are implemented for the Carriage Motor
driver and the Vacuum Fan.
 The Main PCA comes with fully protected motor drivers for
Carriage, Paper-Axis, Service Station and IDS motors. Any
short-circuit will be detected and protected.
 Trailing Cables come with an interlock loop that will prevent
from turning on voltages in the Carriage while the Trailing Cable
is not properly connected. A similar approach of using an
interlock pair is used in the Interconnect Cable to ensure it is
properly connected.
 The EIO slots do not allow for hot insertions while the machine is
powered. That is why it is very important to always power-off
the Printer before inserting the EIO Card or the Formatter
or else the Main PCA could be burned.
 Serial channel, to be used for line production and service
purposes only, will be isolated from Kayak pins with a GPIO in
the Navata ASIC.