CANOGA PERKINS 2270 Fiber Optic Modem - Manual (Page 37)

37
2270 Fiber Optic Modem
This interface has strap option jumpers to configure the RLSD Output at J1-8/10 (DB-25) to sup-
port the KG-194 Resync functionality. Jumper straps W10/W11 (adjacent to U11) and W12/W13/
W14 (adjacent to U8) implement this function (refer to Table 3-L). Jumper straps W10/W11 control
the ON/OFF level and W12/W13/W14 configure the RLSD Output to Bipolar (+6 V and -6 V) or
single-ended (+6 and 0 or -6 and 0).
The W1/W1 strap connects chassis ground to signal ground (W2 position), connects chassis
ground through 100 ohms to signal ground (W1 position), or isolates chassis ground from signal
ground (jumper out). The W5, W6 and W7 jumpers, when installed, ground the midpoints of the
100 ohm termination resistances of the FIFOCLK, SCTE and TxD line receivers. These jumpers
may provide improved performance in cases where the RS-422 inputs are bipolar rather than the
more common unipolar types. The W8, W9 and W15/W16 jumpers are used for converting to the
Legacy configuration (see Figure 3-11).
Table 3-L. Strap Configurations for Programmable Buffered Interface
STRAP CONFIGURATIONS CD OUTPUT (AT J1-6)
VOLTAGE LEVEL ±1 V
ON/OFF
W11 and W14 +6/-6
W11 and W12 +6/0
W11 and W13 0/-6
W10 and W14 -6/+6
W10 and W12 0/+6
W10 and W13 -6/0