Polaroid SprintScan SS35, Repair Manual

Page: 49 / 187

Slide Scanner Repair Manual Functional Description
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Filter Wheel Driver
The main controller PC board provides a filter wheel driver that receives signals from the
microcontroller. These signals directly drive the filter wheel stepper motor to its applicable
position during scanning and calibration. A photo-sensor (U 4) provides the reference for
properly positioning the filter wheel.
Notes: • Used on original SprintScan 35 and on SprintScan 35 ES up to
serial no. B6xxxxxxD.
• SprintScan 35 ES from serial no. B6xxxxxxE and SprintScan 35 PLUS
uses a light tunnel instead of a filter wheel. This light tunnel concentrates
the light onto the CCD array to lessen noise.
System Interface
System interface consists of a SCSI bus which is used to download signal processing
parameters to the slide scanner and to send processed image data to the host computer.
The SCSI interface provides:
SS35/SS35 ES
Two standard 50-pin female Centronics connectors to connect the host computer via the
provided SCSI cable.
SS35 PLUS
One standard 50-pin female Centronics connector and one 25-pin female DB-25 connector.
A 53C80 interface chip (U26 -SS35/SS35 ES, U32 - SS35 PLUS) on the main controller PC
board provides the single ended asynchronous interface.
The SCSI ID selector (pushbutton - SS35 PLUS) on the back plate of the slide scanner is used
to select the slide scanner's SCSI ID. The slide scanner's SCSI ID is preset at the factory
to 6. SCSI ID position 7 is reserved for the SCSI adapter to which the SCSI device(s) are
connected.
Note: If the preset SCSI value must be changed, refer to the provided User's Guide
for detailed instructions on how to change the slide scanner's SCSI value.
During slide scanner operation, the host computer requests a scan and specifies all
programmable modes and processing via the SCSI interface. The slide scanner returns
image data and system status.