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98Appendix A Technical specifications
Table 32 provides the V.90 modem port cable pinouts.
Table 32 V.90 modem cable pinouts
Pin | Function |
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1 | N/C |
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2 | Tip |
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3 | Ring |
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4 | N/C |
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Single V.35/X.21 WAN interface card
The single V.35/X.21 WAN interface card has a single DB28S connector that provides the signals needed to interface to V.35 and X.21 equipment. Figure 43 on page 98 shows the single V.35/X.21 WAN interface card.
Figure 43 Single V.35/X.21 WAN interface card
CS160011A
You need a DSU/CSU (digital service unit/channel service unit) between the WAN connection and the gateway. You can order a V.35 or X.21 cable to attach to the connector. With this cable, the WAN adapter can function as DTE (data terminal equipment).
Table 33 provides the V.35 cable pinouts. Table 34 on page 100 provides the X.21 cable pinouts. (The pair suffix A or B refers to an individual wire within a twisted pair.)
Table 33 V.35 cable pinouts
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end | Signal name | and conductor | end | Notes |
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2 | TXDA | pair 1A | P |
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14 | TXDB | pair 1B | S |
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