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RS 485 communication Answered

Im trying to communicate with servos that use rs458 to move, Im going to use a chip from here: http://para.maxim-ic.com/en/search.mvp?fam=rs485&793=2.5%20to%205.5|3.0%20to%205.5|5&tree=master probebly the MAX13181. But i need to know what pic micro to use to change the one pulse two pulse from a servo controller to a digital signal that the MAX13181 chip can understand



8 years ago

recently I use a pic with usart protocol (pic18f4585; pins: 26,25) and the max485 (the max13181is a tne pins rs485) I used it because is the most easy and cheap. anyways; you need now that it is a transceiver by turns; if you put RE and DE in high you are transmiting, in down you are reciving.

any pic with usart can be used.

to move the servo:

servo<--PIC18F<--MAX485<--RS485(net by 2 wires)<--MAX485<--(PC or PIC)

to now a data:

servo<--PIC18F-->MAX485-->RS485(net by 2 wires)-->MAX485-->(PC or PIC)

after this you need to make you own protocol to can up you net until 255 modules. to control the servo you need to know the degree/high time. for exaple with my servo that is (high 10u per degree) plus a high time base of 600us.