At first, I disassembled HP ScanJet 5c and found two boards mounted on the scanner chassis. The first one, with power supply and stepper motor driver seemd to be usable in the lightbox. The second one with SCSI logic and controller has been dropped away and replaced by my own controller board. 3 plastic slide blocks has been unscrewed from unmounted carriage (with CCD, optics and lamp).
These slide blocks screwed to the new carriage:
I screwed one optical sensor (AKA photo interrupter) to chassis, it should be triggered when crarriage moved to the start position.
On this photo:
1. stepper motor
2. optical sensor
4. plastic slider blocks
5. piece of tin for optical sensor obturation
On this photo you can see how carriage connected to the belt.
LEDs board schematics
Resistors - 200 Ohm (SMD type 1206), LEDs - Kingbright L-7113UVC.
Controller board schematics
SV1-1 to optical sensor LED anode (+)
SV1-2 to optical sensor LED cathode (-)
SV1-3 to optical sensor phototransistor collector
SV1-4 to optical sensor phototransistor emitter
Optical sensors TCST1103, TCST2103 (Vishay), KTIR0311S, KTIR0411S (Kingbright), etc.
SV2-1 to LEDs board +
SV2-2 to LEDs board -
SV3-1 to green LED (front panel) anode (+)
SV3-2 to green LED (front panel) cathode (-)
SV3-3 to button (front panel)
SV3-4 to button (front panel)
Plug ribbon cable from power supply board to connector CON1.
Controller PCBLEDs PCB 600dpiController PCB 600dpiFirmware for PIC12F629/PIC12F675Source code
// TBD: Description