WaxJet 6100, Service Reference Manual

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Timing pulses can be a function of shaft encoder input or an internal
oscillator. Photocell inputs as well as shaft encoder inputs are
received from the Interface PCB via opto-isolators.
Firmware
Module
The Firmware Module connects directly to the CPU PCB. The
Module will contain the system operating software. The current
production standard is 6100415200, but there are many custom
versions and older versions in use. Always check the firmware
version when working on systems and especially when replacing the
firmware module.
Driver PCB
The Driver PCB communicates to the CPU via a 60-pin ribbon cable.
This bi-directional cable provides Printhead and wax system status
to the CPU for fault detection and display. The LED’s on the board
show visual indication of the status that is being sent to the CPU.
The CPU sends image data and timing pulses train to the Driver
PCB on this cable as well.
The Printhead, wax tank and wax hose heating circuits are
controlled on the Driver PCB. Two “pico” fuses are used to provide
overload protection for the 36 VAC heating circuit voltage on the
Driver PCB. If either of these fuses are open, none of the HEATING
LED’s will light.
Image bitmaps containing message structure are brought into the
FIFO when SE command values are selected. When the photocell
trigger occurs and DELAY value is counted out, the CPU will send
pulse train to Printhead. The pulse train will fire the piezocrystals,
ejecting small drops of wax in dot matrix patterns to the product as it
passes in front of the Printhead.
Interface
PCB
Connected to the CPU by a 34-pin ribbon cable, the Interface PCB
mounts to the Connector Panel and connects the system to all
peripherals and supplies 12 VDC for those peripherals. The Front
Port connection will supply the hand held terminal with 5 volts from
CPU circuits as well. The 12 VDC is fused with poly switches and
green LED’s indicate when voltage is present.
Theory of Operation 3-3