how far max232 can travel

Discussion in 'The Projects Forum' started by sasek, Feb 19, 2010.

  1. sasek

    Thread Starter Member

    Jan 3, 2010
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    im using max232 2 make connection betwen PIC and PC, here i want using max232 to make far connection betwen both of them. The problem is, i dont know how far data can go with max232 without repeater like max485........someone pls help me about the distance max232 can go........:)
     
  2. beenthere

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  3. blueroomelectronics

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    How far do you need?
     
  4. sasek

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    Jan 3, 2010
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    i want used about 100m. Mean that max232 and rs485 almost same in function???
     
  5. blueroomelectronics

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    Too long for RS232. RS422 & RS485 can do that distance.
     
  6. Papabravo

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    Feb 24, 2006
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    I could be wrong, but I think RS-485 and LVDS are two entirely different things.
     
  7. DickCappels

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    Aug 21, 2008
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    I had one that traveled nearly 14,000 miles. How did this happen? The first 8,000 miles was in my luggage from the U.S. to Thailand, and the next 6,000 miles was by express mail from Thailand to Scottland.

    More seriously, the MAX-232 should work fine over a distance of 100 meters if you use a low enough data rate. The type of wire (mostly the capacitance between the conductors and the resistivity per unit lenght) will have a lot to do with the maximum data rate.

    One thing to be aware of is that with longer runs, you will increase your chances of data corruption from noise sources and you will increase your chances of damage from nearby lightning, so use appropriate precautions.
     
  8. beenthere

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    Yes. RS-485 uses differential signaling, but the LVDS standard is distinct from that. Should have said that RS-232 is single ended, and RS-485 is differential.
     
  9. sasek

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    Jan 3, 2010
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    i still confius, so what i suppose to do???? the circuit of rs485 is quit difficult to understand
     
  10. beenthere

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    We are also confused.
    Until you give some idea about the separation in the "far connection", we have no idea about the distance.
     
    Last edited: Feb 20, 2010
  11. Papabravo

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    Feb 24, 2006
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    Are you kidding? RS-485 uses a differential signal bus, and the transceiver chips provide you with a transmitter and a receiver. You do need to terminate the bus at each end. It is not full duplex, but you can go further than 25 ft. or 10 m which are the two rules of thumb for maximum distance on RS-232 at low to medium baudrates (1200-19200). You also did not mention how fast you want to go.
     
  12. blueroomelectronics

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    You could use RS422, this is very easy to implement as a RS232 replacement for long distance bidirectional communications.

    www.rs485.com has several adapters, schematics etc...
     
  13. Papabravo

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    Feb 24, 2006
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    Point is that none of these methods should be a source of confusion since they are all implemented with COTS(Commercial Off The Shelf) transmitter/receiver/transceiver chips. The datasheets have typical operating circuits and the manufacturers application notes make using them a cinch. I don't know where the confusion comes from. Can 'ya 'splain it to me one more time, cuz I'm just a poor old country boy without 'yer book larnin.
     
  14. sasek

    Thread Starter Member

    Jan 3, 2010
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    hahahahah thanks 4 helping

    did max232 and rs485 work in almost same concept
    ??????
     
  15. retched

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    Dec 5, 2009
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    Yes, they both use wires.
     
  16. t06afre

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    May 11, 2009
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    Just a few words. For better understanding of the circuits read abou or Google RS232 and RS485. Then take a look at the voltage specifications. Also how do plan to connect your RS485 signal to your RS232 serial port input?
     
  17. beenthere

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    And we still have no idea at all about the dimension of "far distance".
     
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