Rs485 & uPSD3334D

luigi2 · ‎2005-05-10

Posted on May 10, 2005 at 17:32

Rs485 & uPSD3334D

luigi2 · ‎2011-05-17

Posted on May 17, 2011 at 12:06

I must connect three units with protocol master\slave

have any example code function, for the serial comunication in 8051 whit the rs485 protocol?

I would create a netwarok with 1 master and more slave, the slave measuring 4 o 5 parameters (Example:voltage,temperature, exc) and send at the master this data only when it comes to it asked, but if are an allarm (example temperature > 30 Â°C) it send only the name of alarm sensor.. the data line is an rs485

I use uPSD3334D

rk1 · ‎2011-05-17

Posted on May 17, 2011 at 12:06

hi,

rs485 is not a protocol, but a ''physical layer''.

you should handle the rs485 like a ''normal'' uart (rs232) from the 8051.

(see UART-section in the datasheet.)

the rs232-rs485-conversion has to take place outside of the uPSD33xx.