Figure 4 (below) shows the location of jumpers JP4 and JP5 on the
Model 1206RC front card.
JP5: Clock Source (Port A)
The setting for jumper JP5 determines–with respect to Port A–
whether clocking is internal or external. Note: Only Port A may be set
for external clock.
JP5 (Port A)
Setting
Position 1&2
External Clock
Position 2&3
Internal Clock (factory default)
Strap Removed
Not a valid setting
JP4: Clock Source (Port B)
The setting for jumper JP4 determines–with respect to Port B–
whether clocking is internal or receive loopback. Note
1
: If Port B is set
for receive loopback clock, Port A must be set for external clock.
Note
2
: Port B may not be set for external clock.
JP4 (Port B)
Setting
Position 1&2
Receive Loopback Clock
Position 2&3
Internal Clock (factory default)
Strap Removed
Not a valid setting
6
S1 through S3: Data Rate Setting
Switches S1 through S3 are set in combination to determine the
synchronous data rate for the Model 1206RC. Switch S4 is not active.
S1
S2
S3
S4
Setting
Off
Off
Off
N/A
32 kbps
On
Off
Off
N/A
48 kbps
Off
On
Off
N/A
56 kbps
On
On
Off
N/A
64 kbps
Off
Off
On
N/A
72 kbps
On
Off
On
N/A
112 kbps
Off
On
On
N/A
128 kbps
On
On
On
N/A
144 kbps
3.3 FUNCTION CARD JUMPERS
The Model 1206RC has two ports (Port A and Port B), which must
be configured independently for clocking. As Figure 3 (below) shows,
each configuration jumper has three possible positions: strap covering
posts 1 & 2, strap covering posts 2 & 3, or strap removed altogether.
The detailed descriptions for jumpers JP4 and JP5 present all valid
strap positions.
5
Figure 4.
Jumper locations on Model 1206RC front card
JP4
JP5
Figure 2.
Model 1206RC DIP switch orientation on internal daughterboard.
Figure 3.
Possible function card strap positions
On
4
3
2
1
Top of Card
1
2
3
Front of Card
1
2
3
1
2
3
