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Title: Communication using MAX232 Post by: king on April 04, 2010, 09:19:46 09:19 Hi
Actually when i have read the help file of "Proton" then in serout and serin command help file they have used the sentence that "MAX232 inverts the serial polarity" what does it mean? Because if PC is transferring data "11001101" (-12v,-12v,+12v,+12v,-12v,-12v,+12v,-12v) then after max232 we will get (+5v,+5v,0v,0v,+5v,+5v,0v,+5v) again "11001101" so how max232 inverts serial polarity.Please explain it Regards King Title: Re: Communication using MAX232 Post by: oldvan on April 04, 2010, 10:18:40 10:18 TTL level serial +5 is "1" and 0V is "0"
RS232 level -12 is "1" and +12 is "0" So MAX232 does the conversion correctly. Title: Re: Communication using MAX232 Post by: odsk on April 05, 2010, 04:37:56 16:37 Hi
I think the MAX232 will invert the polarity also, check the datasheet and the block diagram you will see that they represent it like an inverter. odsk Title: Re: Communication using MAX232 Post by: shibuv on April 07, 2010, 11:33:58 11:33 Hello All outputs are inverted but you don't bother about it if you communicate with PC see the digram http://picmicrochip.blogspot.com/2010/01/how-to-interface-pic16f877a-18f452-with.html (http://picmicrochip.blogspot.com/2010/01/how-to-interface-pic16f877a-18f452-with.html) shibuv Title: Re: Communication using MAX232 Post by: DreamCat on April 08, 2010, 03:07:09 15:07 Actually, you don't need consider the inverter, RS-232 standard and MAX232 only is a middle process, only if you want use discrete components build the tranceiver.
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