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11 years, 1 month ago.
serial protocol connection
i need to communicate microcontroller lpc 1768 with a serial protocol (RS 485) as my serial protocol (RS 485) is reciving data from smart meter
3 Answers
11 years, 1 month ago.
You can use RS485 using a normal mbed Serial object and a DigitalOut to set the direction of the RS485 transceiver. Which is the second component you need: An RS485 transceiver like the MAX485
thanks for ur help sir but, can you put that in more simple words and what do u mean by digitalout to set direction of the rs 485 transceiver ???
posted by 17 Oct 2013See the datasheet of for example the MAX485: http://datasheets.maximintegrated.com/en/ds/MAX1487-MAX491.pdf, page 7.
You need to enable the driver and receiver of it, depending if you are transmitting or receiving. In principle you may always receive, as long as your code knows you will also receive everything you send. And then with a DigitalOut you can enable the driver when you want to send data.
posted by 18 Oct 2013
10 years, 11 months ago.
Hello, I'm interesting about this subject. Because I need to connect with a equipment in RS485 link. But I don't have very clear how I can do it. I belive that a good idea is to start with an example to coonect 2 mbed's in RS485. Are there someone how can give some exemple about this subject?
Thanks so much
AJ
10 years, 9 months ago.
many thanks As i need to connect my smart meter to my mbed-board (lpc1768) so i am using ethernet connection between meter and board. modbus protocols are need to write on boared to revive information from meter. thanks