| ??? 12/27/04 13:33 Read: times |
#83928 - comments on speed and the above Responding to: ???'s previous message |
so rather than pile as many devices onto the one bus, split it up and use a rs485 hub (or design your master to have many drivers). If you put rx & tx leds on each bus, you'll be able to see which one has died quickly and from then isolate the defective slave. I also recommend putting rx & tx leds on the slaves - it helps debug problems quickly. The usual problem is the + & - signals swapped, the rx led stays full on in this instance.
My method is to have two connectors and auto-termination on each node, it has the following advantages: 1) if problem, unplug anywhere, if it works: problem downstream, if not: problem upstream. 2) with 2 connectors, you can have "zero length" stubs. On speed: I have found the speed of the UART irrelevant, you can not run faster than your ISR code. Erik |
| Topic | Author | Date |
| Control system | 01/01/70 00:00 | |
| buses for industrial | 01/01/70 00:00 | |
| CAN or RS-485 | 01/01/70 00:00 | |
| one way of master slave | 01/01/70 00:00 | |
| RS485 | 01/01/70 00:00 | |
| Control system | 01/01/70 00:00 | |
| Modbus | 01/01/70 00:00 | |
| modbus or not | 01/01/70 00:00 | |
| rs-485 | 01/01/70 00:00 | |
| Rs485 vs CAN | 01/01/70 00:00 | |
| CAN | 01/01/70 00:00 | |
| rs-485,high speed? | 01/01/70 00:00 | |
| UART speed | 01/01/70 00:00 | |
| Speed | 01/01/70 00:00 | |
| Go Speed Racer! | 01/01/70 00:00 | |
| comments on speed and the above | 01/01/70 00:00 | |
| Daisy chain | 01/01/70 00:00 | |
| Daisy,Daisy..... | 01/01/70 00:00 | |
| no repeat | 01/01/70 00:00 | |
| Modbus | 01/01/70 00:00 | |
| Modbus | 01/01/70 00:00 | |
| Hub ? | 01/01/70 00:00 | |
| Modbus | 01/01/70 00:00 | |
| Modbus | 01/01/70 00:00 | |
| More modbus | 01/01/70 00:00 | |
| Modbus | 01/01/70 00:00 | |
failed links | 01/01/70 00:00 |