Omega Engineering RS-422/485 用户手册
Card Setup
OMG-ULTRA-COMM422
Page 10
Clock Modes
The OMG-ULTRA-COMM422 employs a unique clocking option that allows the
end user to select from divide by 4, divide by 2 and divide by 1 clocking modes.
These modes are selected at Headers J1C through J4C.
end user to select from divide by 4, divide by 2 and divide by 1 clocking modes.
These modes are selected at Headers J1C through J4C.
To select the Baud rates commonly associated with COM: ports (i.e. 2400, 4800,
9600, 19.2, … 115.2K Bps ) place the jumper in the divide by 4 mode (silk-screen
DIV4).
9600, 19.2, … 115.2K Bps ) place the jumper in the divide by 4 mode (silk-screen
DIV4).
DIV1
DIV2
DIV4
Figure 12 - Clocking Mode 'Divide By 4’
To double these rates up to a maximum rate for 230.4K bps place the jumper in
the divide by 2 (silk-screen DIV2) position.
the divide by 2 (silk-screen DIV2) position.
DIV1
DIV2
DIV4
Figure 13 - Clocking Mode 'Divide By 2’
To select the maximum data rate (460.8K bps) place the jumper in the divide by 1
(silk-screen DIV1) position.
(silk-screen DIV1) position.
DIV1
DIV2
DIV4
Figure 14 - Clocking Mode 'Divide By 1’