Impulse 7204 User Manual
Page 9
Card
Setup
Sealevel Systems ULTRA 485+2.PCI Page
6
Clock Modes
The ULTRA 485+2.PCI 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.
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).
DI
V
1
DI
V
2
DI
V
4
Figure 7- 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.
DI
V1
DI
V2
DI
V4
Figure 8-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.
DI
V1
DI
V2
DI
V4
Figure 9-Clocking Mode 'Divide By 1