Kodak 800 SERIES service manual Main PWA LED Status Indicators

NovaJet 800 Series Service Manual

Main PWA LED Status Indicators

D1 - Normally flashes when the DSP is idle. Steady during print opera- tions.

D8 - +24V available.

D9 - Normally flashes when the Power PC processor is idle. Stops flashing when processor is busy (i.e. during paper sensing operations or printing).

D10 - Normally OFF; Flashes during initialization, then turns off. LED staying on would indicate a problem when the FPGA is unconfigured. Ensures the gate array chips have been properly programmed (one on Main PWA and on each Carriage PWA).

D13 - +5V available.

Microprocessor (CPU)

The microprocessor (a 48MHz PowerPC 860 from Motorola) is the central processor unit which supervises system functions, executes the printer firmware, manipulates data, and controls input/output data busses. It has four built-in serial ports, a two channel DMA (Direct Memory Access) controller, a timer module, clock generator, and an on-board chip select generator. The serial ports are not used and are disabled in all shipping firmware. One DMA channel is used to receive data through the parallel port via the gate array. One timer generates a servo interrupt every millisecond; another is used to coordinate firmware multi-tasking.

The chip select generator is programmed to generate chip selects at the appropriate addresses, with the appropriate data size (byte, word) and with the appropriate number of wait states.

Theory of Operation 2-8