CHAPTER 4: Ground Strap and Pin Connections
4.Ground Strap and Pin Connections
4.1Ground Strap
Signal grounds (Pins 19, 20, and 37 on the 422 interface and Pin B on the V.35 interface) are connected together, but not connected to chassis ground (Pin A). However, for applications requiring the grounds at a common reference point, the grounds can be connected by installing a jumper strap across W3 located at the rear of the printed circuit board between J1 and P1.
CHASSIS GROUND | A | B | SIGNAL GROUND |
REQUEST TO SEND | C | D | CLEAR TO SEND |
DATA SET READY | E | F | RECEIVE LINE SIGNAL DETECT |
DATA TERMINAL READY | H | J | LOCAL LOOPBACK |
TEST MODE | K | L | TEST PATTERN |
TRANSMITTED DATA | P | R | RECEIVED DATA |
TRANSMITTED DATA | S | T | RECEIVED DATA |
TRANSMIT TIMING | U | V | RECEIVE TIMING |
TRANSMIT TIMING | W | X | RECEIVE TIMING |
TRANSMIT TIMING | Y |
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TRANSMIT TIMING AA | BB | REMOTE LOOPBACK | |
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Figure 4-1. V.35 Interface
RECEIVE COMMON 20 | 1 | SHIELD | |
2 |
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21 |
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3 |
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SEND DATA 22 |
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4 | SEND DATA | ||
SEND TIMING 23 | 5 | SEND TIMING | |
RECEIVE DATA 24 | |||
6 | RECEIVE DATA | ||
REQUEST TO SEND 25 | |||
7 | REQUEST TO SEND | ||
RECEIVE TIMING 26 | 8 | RECEIVE TIMING | |
CLEAR TO SEND 27 | 9 | CLEAR TO SEND | |
28 | |||
10 |
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DATA MODE 29 |
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11 | DATA MODE | ||
TERMINAL READY 30 | 12 | TERMINAL READY | |
RECEIVER READY 31 | 13 | RECEIVER READY | |
32 | |||
14 |
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3315
3416
TERMINAL TIMING 35 | 17 | TERMINAL TIMING | |
36 | |||
18 |
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SEND COMMON 37 |
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19 | SIGNAL GROUND | ||
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Figure 4-2. RS-422 Interface.
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