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4-PORT RS-232 PCI AND HS PCI SERIAL ADAPTERS
3. Card Setup
3.1 Clock Modes
The adapter 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. This mode is
selected at J2.
To select the baud rates commonly associated with COM ports (2400, 4800,
9600, 19.2, … 115.2 kbps), place the jumper in the divide by 4 mode (marked
DIV4).
Figure 3-1. Clocking mode “Divide by 4.”
To double these rates up to a maximum rate for 230.4 kbps, place the jumper in
the divide by 2 position (marked DIV2).
Figure 3-2. Clocking mode “Divide by 2.”
To select the maximum data rate (460.8 kbps) place the jumper in the divide by 1
position (marked DIV1).
DIV1
DIV2
DIV4
DIV1
DIV2
DIV4
