| ??? 09/18/08 15:51 Read: times |
#158366 - half-duplex networking Responding to: ???'s previous message |
The hazards of using half-duplex RS-485 is that if any node fails in transmit mode it will jam the entire network. From the description I would guess a particular controller fails with the transmit enable line to the MAX1483 turned on. It's not the MAX1483, it's the 89C51 that's the problem.
For 24/7 reliability you will need some kind of watchdog/failsafe circuit that ensures the RS-485 transceiver disconnects if the controller fails. You might look at using some kind of one-shot to enable the transmit, which then times out until the next enable pulse from the controller. |
| Topic | Author | Date |
| MAX1483 problem | 01/01/70 00:00 | |
| and terminated?? | 01/01/70 00:00 | |
| Comm Packet Receive Validation | 01/01/70 00:00 | |
| I agree with Michael | 01/01/70 00:00 | |
| Sorry Erick, Couldn't reply you earlier | 01/01/70 00:00 | |
| how did you do that with a PC as the master? | 01/01/70 00:00 | |
| 9 bit | 01/01/70 00:00 | |
after I posted | 01/01/70 00:00 | |
| half-duplex networking | 01/01/70 00:00 | |
| Watchdog function common | 01/01/70 00:00 | |
| Only one transmitter at a time. | 01/01/70 00:00 | |
| suggest from third countries... | 01/01/70 00:00 | |
| Something else to consider | 01/01/70 00:00 | |
| too late, but for others | 01/01/70 00:00 |