Scalar 218
Theory of Operation
adic
Service Procedure
63-1181-01 Rev A
3
l
Provides a monitor function, mirroring SCSI commands and inter-processor commands via serial
port Comm 1.
l
Maintains the operational logs stored in the NVRAM.
l
Communicates commands and receives status from the
Motion Processor
via the inter-
processor serial communication port.
Motion Processor
The
Motion Processor
contains code in it’s internal EPROM (Boot Code) which has elemental inter-
processor communication, diagnostic LED control, and keypad I/O capability. During the boot process,
the
Motion Processor
communicates with the keyboard as dictated by the
Main Processor
. When
commanded by the
Main
Processor
, the
Motion Processor
switches to operating code in it’s RAM
memory (see Main Processor description on previous page).
Once executing the code in its RAM memory, the
Motion Processor
performs the following functions:
l
Initializes all ports and registers.
l
Maintains position tables for the X-axis coordinates of the
Media Picker
assembly and relates
them to element addresses as assigned in the SCSI interface specification.
l
Monitors position by maintaining X-axis coordinate counts from the X-axis encoder interrupts.
l
Calculates position offsets for motion commands received from the Main Processor and
communicates them to the
Micro-Stepper Processor
.
l
Writes a binary pattern to the Diagnostic LED’s (located on the Main Controller board) associated
with currently active firmware processes.
l
Writes data to the keyboard, and LED’s. Reads switch information after an interrupt, reads door
open sensors and cartridge present sensors on a polled basis.
l
Controls and monitors the
Picker Processor
via one of the two serial ports.
l
Controls the Drive Mux Bus. Selects the appropriate drive assembly, monitors the assembly’s
serial stream information via the assembly’s serial multiplexer board, monitors the drive door
switch status via the Drive Mux Bus, and controls the
Door
Open Stepper Motor
via the Drive
Mux Bus.
Picker Processor
The
Picker Processor
, mounted inside the Media Picker, interfaces to the
Motion Processor
via a
balanced differential serial port. The
Picker
Processor
controls the following picker functions:
l
Monitors
Media Picker
Entry/Exit Port
cartridge sensors.
l
Monitors and keeps track of the Gripper Carriage position via the three carriage optical sensors.
l
Controls the enable and direction of the gripper motor. Monitors the gripper limit signal which
indicates that the jaws have stalled or reached a limit.
l
Controls the enable, direction, and break of the roller motor.
l
Controls the enable, direction, and break of the carriage motor.
l
Controls the trigger on the Barcode reader and monitors the serial Barcode reader data.
