MAX232 bad?

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bluejunkpile
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MAX232 bad?

Post by bluejunkpile »

hi all and thank you for your patients. i have MS2 v3 that was build by someone else. in my process of double checking build,i am at the point of verifing serial comunication and it doesn't pass the final loopback comunications test. when i tested a db9 cable and serial port on my computer, the port and cable pass the test. i also have a RS232 to USB adapter from DIYAutoTune that passes as well. i was going through all the troubleshooting steps, everything checks out. i have tried two separate computers and still no comunications. the only tests that i am unsure of are the voltage tests at the MAx232. does this sound like a bad MAX232? your help is most welcome.
Matt Cramer
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Re: MAX232 bad?

Post by Matt Cramer »

It could be, but first make sure you've got 5 volt power.
bluejunkpile
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Re: MAX232 bad?

Post by bluejunkpile »

i have my 5v on the board where it suppose to be. which pin on the max232 am i suppose to have 5v? that's where i get a little confused, on the max232,what voltages should i have on which pins. i really would like to fix this board rather than build another. thanks so much!
trakkies
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Re: MAX232 bad?

Post by trakkies »

http://www.megamanual.com/ms2/pcb.htm

Drawing (Sheet) 8 of 8 is the section of the schematic you want.
Dave P, London UK.
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bluejunkpile
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Re: MAX232 bad?

Post by bluejunkpile »

Thanks guys! Hopefully this will shed light on the problem.
bluejunkpile
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Posts: 4
Joined: Tue Aug 30, 2011 6:02 pm

Re: MAX232 bad?

Post by bluejunkpile »

last night I replaced the max232 and c26-29 as per instructions, and it's fixed.I want to thank you for your help!
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