Epson EPL-9000 Service Manual page 82

Principles
2.2.1.10 Video Interface
The maps the
CPU transmits data from the V-RAM
The cell converts the image data in the
then transmits it to the engine controller board. In other words, the
used to transmit the image data to the engine controller board. This serial image data is called the
VIDEO signal of video interface.
The signal line of the internal video interface
board) can be broadly divided into four groups. The first group (PRINT,
gives the status of either the video controller or engine
ready to communicate with each other or ready to start the printing
(TOP, is the synchronizing signal for the printing operation. The third group (VIDEO) is the
serial video data signal. The fourth group
commands (from the video controller) or the status (from the engine controller) for printer
mechanism control. Except for VIDEO, PRINT, TOP, and
E05A93.
This printer has
signal with the
2-30
into a memory space different from the system memory. The
the system RAM) to the W using the
and functions standard. These functions modify the VIDEO
from parallel to serial, synchronizes it, and
is a temporary buffer
(the MAIN board and engine controller
and indicates whether they are
operation.
and is used to transfer the
signals are controlled by
RDY, and PRD)
group
second
Rev.