Electronics Packaging; System Architecture - AGFA Avantra 36/44 Service Manual

Avantra 36/44 Service Manual
The OCP module, which contains a dedicated micro-controller, is the main control-
ler of the system. User commands originating from the RIP and/or the operator are
verified, parsed and either acted upon by the OCP or passed to the DEC. The pars-
ing process includes breaking the macro language of the user into a micro language
that is more easily implemented within the engine controller.
The DEC reacts to the micro commands by activating the electromechanical devices
within the imagesetter to move media, control the carriage, image media, and gen-
erally monitor system operations.

2.3.1 Electronics Packaging

The electronics are packaged on a single main PC board (DEC) with satellite boards
providing driver/sensor control for motors, carriage, and laser drive. The DEC con-
tains all the circuitry for the APIS input, image control, slow scan control, spinner,
and media system controls. Various communication channels are also supported.
Two PC boards reside on the carriage assembly:
• Carriage Sensor Driver Module (CSDM)
• Laser Driver Module (LDM)
The CSDM is responsible for the driver and sensor controls for the carriage servo
drive and encoder. It also passes power and electronic signals from the DEC to the
LDM. The LDM provides power and control for the laser diode.
Two more PC boards reside within the imagesetter. These boards provide driver/
sensor control for the Media Transport system called the Sensor Driver Modules
(SDM). The two boards are identical, with one controlling the supply side and the
other controlling the take-up side.
The OCP PC board plugs directly into the back of the touch screen display. The
OCP provides the electrical interface between the user and the DEC board to carry
out commands input at the control panel.

2.3.2 System Architecture

The SPI bus in the Avantra architecture is organized so that only a single micro-con-
troller can be a bus master at any one time, with the remaining controllers as slave
devices. At power-up the DIAG micro-controller is configured as the master
device. It initializes the whole system, performs some basic confidence checks,
and then gives up its mastership role to the DEC K-1.
Communications between slave controllers must first go through the master micro-
controller. Usually the DEC K-1 coordinates the inter-processor tasks in the system.
For example, if the DEC K-1 is the master and the OCP wants service from the DSP,
the OCP must first notify the DEC, which then passes the service request to the
DSP. After the service is performed, the DSP sends the result to the DEC, which
then forwards it to the OCP.
Each micro-controller performs specific tasks in the system. The main tasks per-
formed by each micro-controller in the Avantra system are described next.
2-4 Functional Analysis