MICROTRONIX DX-2200-SW-02, Руководство пользователя

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DX-2200
– Dual-view 2x1 SDI Video Switcher
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‘nnn’ – is a three digit number between 000 and 255 where 000 is
0% transparent and 255 is 100% transparent
B
AUD
R
ATE
SERIAL C
OMMAND
The DX-2200 always powers up at 115200 baud. After power up, the baud rate
can be changed using the MBnnnnnnn command, where nnnnnnn is the new
baud rate between 9600 and 1000000 baud.
The response to the baud rate command is transmitted before the baud rate is
changed. It is recommended to wait 100 ms after receiving the response before
sending commands at the new baud rate to ensure the DX-2200 is ready to
receive commands at the new rate.
Note: The DX-2200 always starts at 115200 baud. Changes to the baud rate cannot be
saved to flash.
Table 7: Baud Rate SERIAL Command Codes
Command Code Mode of Operation
Baud Rate Control Commands
MBnnnnnnn
Set the baud rate to nnnnnnnn where nnnnnnnn is a
number between 9600 and 1000000 baud.
G
RAPHIC
O
VERLAY
SERIAL C
OMMANDS
The Graphic Overlay layer can display up to 48 user-defined Graphic Fields. Each
Graphic Field can be configured to be Text, Rectangle, Corner Marker, Target
Marker, or an Image Field. The fields can be configured and positioned using the
Graphic Overlay Serial Commands below.
The Graphic Overlay utilizes two frame buffers located in memory. One of these
frame buffers (the active buffer) generates a video output that is mixed on top of
the input video, while the other buffer (the spare buffer) is prepared for use.
The video output of the layer is updated by rendering all Graphic Fields into the
spare buffer using the parameters that have been set for each Field. The amount
of time required to render the text to the spare buffer depends on the number of
pixels that must be drawn. Typically, the rendering process takes more than one
frame to complete. During this time, the active buffer continues to provide the
Graphic Overlay video output. After rendering is complete, the DX-2200 switches
the active and spare buffers. The buffer that was active before the update
becomes the new spare buffer and is cleared by the unit to so that it is ready for
text to be rendered again when the next update occurs. Buffer switching is always
performed at the end of frame.
Many of the Graphic Field commands update the parameters of a Field (for
example the visibility, color or transparency), but do not update the video output.
This allows the user to change as many parameters as required before sending a
command to show the updated output.