| ??? 05/28/08 04:43 Read: times |
#155198 - It's just another way to get the job done. Responding to: ???'s previous message |
Erik Malund said:
kind of derives its own direction control. if you treat it carefully. If you don't treat it carefully, you get what you deserve. I thoroughly read the datasheet a while ago and the above is what I read.
If you do not (as with any other 485 implementation on a '51) have the proper waits between transmit from a and transmit from b it will, of course, fail. As you might expect. I'm not sure I'm understanding what you mean by A and B. This is a single differential transceiver, hence A=/B and vice versa. Is the skew between those two what concerns you? This chip is more critical in that respect than a 'regular' "direction pin transceiver" and and as you have to determine the 'when' anyhow, where is the advantage? Primarily, it's in that you don't have to have an isolated enable. It's just another device for the task, but it does regulate its own supply, and make that available for use by the optoisolators, which helps with cost and complexity. Erik
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| Topic | Author | Date |
| RS485 questions | 01/01/70 00:00 | |
| Yes its required | 01/01/70 00:00 | |
| + | 01/01/70 00:00 | |
| you can not achieve isolation .... | 01/01/70 00:00 | |
| + | 01/01/70 00:00 | |
| why common power and isolated 485? | 01/01/70 00:00 | |
| where to get supply | 01/01/70 00:00 | |
| RS485 experiences | 01/01/70 00:00 | |
| all the stuff inside | 01/01/70 00:00 | |
| Prifibus alike | 01/01/70 00:00 | |
| not with '176 | 01/01/70 00:00 | |
| sn75lbc176 planed | 01/01/70 00:00 | |
| why galvanic isolation ? | 01/01/70 00:00 | |
| what is wrong? | 01/01/70 00:00 | |
| then try MAX3158 | 01/01/70 00:00 | |
| how about this little gem? | 01/01/70 00:00 | |
| have you read it fully | 01/01/70 00:00 | |
| It's just another way to get the job done. | 01/01/70 00:00 | |
| OK, I'll bend it in neon | 01/01/70 00:00 | |
| Prifibus alike ..... it isn't | 01/01/70 00:00 | |
| Galavanic isolation | 01/01/70 00:00 | |
| Galavanic isolation | 01/01/70 00:00 | |
| Do it like Profibus | 01/01/70 00:00 | |
| economical approach | 01/01/70 00:00 | |
Thanks for all answers! | 01/01/70 00:00 |