Clock Modes - Black Box 2-Port RS-232/422/485 User Manual

3.5 Clock Modes

The Adapter employs a clocking option that allows you 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 (for example,
2400, 4800, 9600, and 19,200 bps, and so on up to 115.2 kbps), place the jumper in
the "divide by 4" mode (marked DIV4).
To double these rates, so that the Adapter can communicate at up to a
maximum rate of 230.4 kbps, place the jumper in the "divide by 2" position
(marked DIV2).
DIV1
DIV2
DIV4
Figure 3-8. Clocking mode "divide by 4."
DIV1
DIV2
DIV4
Figure 3-9. Clocking mode "divide by 2."
CHAPTER 3: Card Setup
15