Knowledgebase Article
| Knowledgebase > Connectivity > Connect IT > Microproducts and General Communications Equipment |
|
||
| What's required for a Short Range Multipoint Modem to operate Two Wire? | |||
| Article Id #: 261 | |||
First of all, the communication equipment must control Request To Send (RTS). This is very important, when a modem detects an ON (+ voltage) on Pin 4 (RTS) it switches the transmitter from High Impedance to Low Impedance. If two or more pieces of equipment have RTS - ON, the line will be clamped and there will be no transmission possible. These modems operate in Half-Duplex only when they are configured for Multi-Point operation. For Half-Duplex operation all equipment must have RTS-OFF, a negative voltage on Pin 4 of the RS-232/V.24 serial port. Typical Half Duplex communications will function as follows:
A Master unit will Poll with addresses of slave units. The Master unit turns ON RTS sends the address of a slave unit, turn RTS OFF. The Slave unit receives it's address, turns ON RTS sends the information then turns OFF RTS. |
|||
| User Rating | |||
 This answer was helpful |
 This answer was not helpful |
(8778 vote(s))
|
|
| User Comments ( Add a Comment ) | |||
