Epson ActionLaser 1300, Руководство по обслуживанию

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/Action Laser 1300 Service Manual
Operating Principles
Print data and commands transmitted from the host computer via parallel or optional interfaces are
read using the interrupt process of the CPU and are stored in the DRAM input buffer.
Data and commands in the input buffer are processed by the CPU, which then stores the printing
bit-map data (image data) in the V-RAM (Video RAM) (image buffer) in the DRAM. The size of the
V-RAM depends on the available DRAM size and can be specified using printer settings. A page
error occurs when the V-RAM is so small that the CPU cannot process data faster than it is
transmitted to the engine controller board. If such an error occurs, increase the V-RAM using
printer settings.
The CPU transmits image data stored in the V-RAM to a temporary buffer in the which is
located in an address space different from the CPU.
The temporary buffer has a capacity
equivalent to several lines. This is controlled by the which synchronizes and transmits the
d a t a t o
-
has and toner save functions.
CPU
68000
Development
Host Computer
I
Parallel Circuit
I
E05B01
I
I
E05A83
DRAM Parallel/Serial
Control Converter
Circuit
Temporary Buffer
I
I
,
I
I
➤
: VRAM
(Band buffer/
System
Area
Input Buffer page buffer)
Figure 2-32. Data Flow Diagram
Toner Save
Engine
Controller
Circuit
Rev.
2-21