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Roel_Wessels

FSBUS MAX232 Types

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Hi everyone,I'm new into posting in this forum, but I've been reading it for about 2 years now. You quys made me anxious enough to get me into cockpitbuilding myself.That is why I started on the FSBUS interface. I've etched two PCB's, The FSCOMIII and the FSLED board to get me started. I got all the components and carefully started soldering.My FSCOMIII seems erronous. It does give out voltages at the PIC on the FSLED board, and it can be altered using the FSBUS software (using the troubleshooting page). It does not respond correctly however to the changes made in the troubleshooting page (It looks like the changes are inverted from what they should be :( ).Before I go into the details of it's behavior to find the probable cause, I want to make sure that my components are correct. After etching I checked all the lines --> OK. After soldering I checked for shorts --> OK. So that's sort of ruled out...On thing I noticed, is that I used the MAX232ECPE which is different than the MAX232CPE which is suggested here ( http://home.hccnet.nl/pa7rm/fsbusparts.htm )Could that be the problem?I know you guys got through it , so maybe you can help me,Thanks in advance,Roel WesselsThe Netherlandswww.huizecook.nl/Vliegvrienden/

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The ECPE version is just a more (then the CPE) protected version against electrical shocks.Your problem may come from an erroneous connection to the serial port.But...Please clarify:>page (It looks like the changes are inverted from what they>should be :( ).do you mean that when you set 5V you have 0and when you set 0 you have 5V ?Or that by changing one pin you are changeing another instead?The second case means you have inverted one (or more) cables from the serial port while makeing the connection to the FSCOM3 card.The first would mean that you have somehow managed to invert the logical state of one or more pins...Can't understand how would you ever achieved it without wanting and knowing how to do it...Clarify this and i'll se if i can help you somehow.

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Thanks Claudio for your fast reply. Glad you're willing to help!The second case (changing one pin changes another) seems more what we are dealing with here...I've made a picture to clarify the problem, it is a picture of the cables and connectors on my FSCOM board.I've also measured the responses of the card, when I change the states of the ports in the troubleshooter, with a voltmeter.I've also got a question regarding the 78L12 transformer (is it called like that in English?)The exact problem description is on my site (because I find it more easily to create a clear page for you to read), along with some other questions of mine. Please respond with you answers on this forum.The page can be found here http://bev02.adsl.utwente.nl/Vliegvrienden...nENProblem.htmlThanks in advance for your help.Roel.

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Ok let's go.The 78(L)12 is not a "transformer" rather a linear voltage regulator.The eventual L means it is the Low-Dropout version.Never mind :)The voltage drop after the diode is right.>Pin 1 is CLOCK(5V), Pin 2 is DATA(5V) and Pin 5 is MCLROk, it's right.Have you used your tester's continuity function to verify against shorts?Disconnect everything, take out the Max232 and verify each pin on the 232 socket, with each pin on the FSBUS connectors.You must be sure there are no shorts connecting one pin of the 232 to more then one fsbus pin.Otherwise these things can happen.Then look again at the scheme and carefully check if the serial connection is ok (i didn't have a flat-cable serial plug, so i manually soldered every cable).I had similar problems when i first finished the Com3 card: after days of struggling i finally found 2 shorts in the crouded area of the FSBUS connectors where it's easy to make mistakes.Anyway in the case you have shorts, the first example you reported would be strange:haveing all the pins active on the card, even when on the software you have them all off is weird, really weird.It seems like there is at least one shoft between Pin5 and Pin1.But then also the action of the pin seem inverted...Mhhh...Go in ControlPanel->System->DeviceManager->PortsOpen the Com port you're using and report here the settings as shown under "port settings".Let's see what comes out.

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I have no idea if it helps at all. But I had to use a 12 volt power supply in order to get mine to do any kind of flashing. Without the 12 volt supply, I could not read the necessary 13 volts needed to flash. Just a thought. Milt

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Thanks you for the answers to my questions.I've added a screenshot of the COM2 port settings (FSbus attached to port 2)http://bev02.adsl.utwente.nl/Vliegvrienden...ortSettings.jpgI hope they're wrong!Milt, I've tried that already. I have a power supply which can be can be set to different voltages. Increasing voltage to 12V makes no difference. It's still weird that it only generates 12,12V instead of the neccesary 13.5V. That's why I think the 78L12 maybe erronous or connected improperly (i.e. upside down). Can anyone shed light into the Vin, GND and Vout pins of the 7812? This problem is discussed on my site http://bev02.adsl.utwente.nl/Vliegvrienden...nENProblem.htmlat the bottom.Thanks,Roel.

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The com ports settings are ok.The 78(L)12 is not responsible for the 13.5V, it can only provide 12V and is used for the rest of the logic on the board (the ne555,max232,etc).The transistor near the first FSBUS connector should be the one responsible for the 13.5V, and that's why i think you need more then 9V of power...I use 15V on mine.

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So what would be the correct pin settings for the 78L12. Should Vin come from the contact nearest to the 7805*which is my current setup) or is that the Vout pin?Thanks for your help. I've tried switching to 12V. Then the MCLR voltage goes up to 14.90V. I quess this is better. I am still working on the project and etched a new board. Maybe this one will do better.Roel.

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Roel,I'd double check the pin assignments between your com port and the fsbus board. I made the exact same cable as you have, and found that most of the wires were one pin higher than they should have been, eg, pin2 on the dsub (9pin) connector went to pin3 on the IDC connector, which is also pin3 on the fsbus board, but should be at pin2. This caused me all sorts of problems when using the fsbus troubleshooter.Hope this helps. I know it did for me, as it worked perfectly as soon as I fixed it. And I have to say, it is deeply rewarding. Now I just need to build the cockpit.Cheers,Dale.

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Looking at the com cable I think you have the same problem that I had.What I would do is check that each pin on the D com port plug is going to the correct pin on the fscom board.I couldn't use the licorice strap system as they aren't correctly aligned for that 2x5 pin layout.

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Greetings AllI'm new to this forum and just thought I'd add my 2 cents. Just a note on the function of the 7812. IT IS what regulates the 13V !!! The voltage generated by the 555 voltage doubler is even higher. It's because of the LED connected to the "common pin". The "output pin" does regulate to 12V, but that in reference to the "common pin". If you add the LED, it'll be 12V plus the LED forward voltage (~1.2V) at the "output pin".I also have a FSBUS question that I hope someone can help me with........ I was testing my COMM III card and was "looking" around in general, and if you "add display" it looks like you can use common anode and common cathode displays. IS THIS TRUE?? If it is, do you wire it it the same and let the software take care of the rest???ThanksGus

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>I'm new to this forum and just thought I'd add my 2 cents.>Just a note on the function of the 7812. IT IS what regulates>the 13V !!! The voltage generated by the 555 voltage doubler>is even higher. It's because of the LED connected to the>"common pin". The "output pin" does regulate to 12V, but that>in reference to the "common pin". If you add the LED, it'll be>12V plus the LED forward voltage (~1.2V) at the "output pin".You are right: in my mind i mistaked the 7805 for the 7812 :(>I also have a FSBUS question that I hope someone can help me>with........ I was testing my COMM III card and was "looking">around in general, and if you "add display" it looks like you>can use common anode and common cathode displays. IS THIS>TRUE?? If it is, do you wire it it the same and let the>software take care of the rest???Absolutely.It's the PIC that provides the correct polarity for driving eighter CA or CC.Notice tough that one of them (i think CA) has a bug: last digit doesn't work.

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Greetings ERUPSThanks for the quick response.... I've commited my PCB to common anode displays. Now I'll just have to keep my fingers crossd!!!!!!Gus B

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Hi all,It has been a while. That's because my ADSL company went bankrupt... The connection will be restored this week so then I can visit the forum regularly.I've redone the FSCOMIII board,redone the connection cable between the COMIII board and the serial port (you guys were right it the cable was a mess looking at the pinout scheme! But it's ok now...),Adjusted the tantal capictors so that the polarity is correct,Adjusted the input power from the power supply to 12V.Here's the deal, the voltages are correct now. (i.e. 5V for the clock and data pins and 13.85V for the MCLR which seems about right)But the troubleshooter window still reveals the same problems. (it does respond, but not correctly, :( )So now I have two FSCOMIII cards which respond equally sh*t!This week when my internet connection is restored, I will report on the behavior of the card.One question in advance :-). I tested the continuity of the lines on the cards, especially the data and clock lines which seem to interupt with each other.The resistance between the two is about 1200kOhm. Is this okay?Also when I apply 5V and the GND directly from the power supply on the clock pin and GND pin respectivily, on the serial cable input pins, I get about 4V on the data pin. Might this be the source of the problem?Thanks in advance,Regards,Roel.

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Ok I've tried all your advices, and some seem to work. As I've said I've now two FSCOM cards which behave equally wrong. I desperatly want them to work! (Or at least one of them ;-) )I still think the cable can be the problem. I've adjusted it as can be seen on the picture below. I used the licorice cable and interconnected the cables in the center to make it sure it's ok.http://bev02.adsl.utwente.nl/VliegVrienden...SerialCable.jpgI am beginning to think that the connection scheme I use may be wrong or outdated ? Can anyone comment on this? This is the one I made based on the one below that.http://bev02.adsl.utwente.nl/VliegVrienden...inoutScheme.gifOriginal version from FSBUS docshttp://bev02.adsl.utwente.nl/VliegVrienden...IISchematic.jpgRoel

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One is nailed:connection from serial port pin 8 goes to pin 8, should instead go to pin 9.Check on the schematic: pin 7 of the MAX232 should be connected to pin 8 of the serial port.In your case it is left unconnected.I can't see any other errors in the serial port connection cable.Hope this can solve your problem!

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Yikes! Claudio, you were right.However, it seems that I made an error drawing the diagram. Because the flat cable unfortunatly has the right connection. I'm very sorry.The thing with the diagram is that I checked and rechecked and still things slip trough. I hate that!Like I said I've made progress because the boards now give out the correct voltages. But the PIC won't flash...I'm almost beginning to feel ashamed asking so many questions. Again, thank you guys so much for your help until now!Now, to get an progress on my FSBus System:What would you do, being in this situation?What are the area's I should look at to get the troubles I have solved? What is most probable?Roel.

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You could try this:disconnect the fscomm from everything, take out the max232, with your tester in "continuity" mode, verify pins 10,11,12 on the max232 socket.Do this:put one lead of the tester in one of the pins of the max232 socket, then use the other to prob for eventual shorts between the differents pins on the FSBUS connectors.Each max232 pin should result continous to only its own signal.Then apply nominal power to the fscomm3 and try applying 12V dc to pins 7 and 4 of the serial port connector, and check that corresponding pins on the FSBUS connectors change from 5V to zero.This should ensure that everything is ok.If that's the case, and your serial cable is ok...I don't know what else to do :(There MUST be something screwed to track down...

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BTW,Pin 10,11,12 what counting do you use?like this16 15 14 13 12 11 10 91 2 3 4 5 6 7 8(which it should be, I think)or did you use9 10 11 12 13 14 15 161 2 3 4 5 6 7 8(which makes more sense in your problem solving scenario)rgds,Roel.

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Ok with the help of Claudio I tried the following:Claudio's Big Troubleshooting Guide:>You could try this:>disconnect the fscomm from everything, take out the max232,>with your tester in "continuity" mode, verify pins 10,11,12 on>the max232 socket.First of all I used these pins:http://bev02.adsl.utwente.nl/VliegVrienden...noutScheme2.gifPin 10 - Is okay: i.e. only one line is continuous, the rest isn'tPin 11 - Is okayPin 12 - Is okay BUT gives 1500kOhm on the GND pin (I think mainly caused by the N4148 diode at the bottom of the board connecting it. This seems to be ok? When I reinserted the MAX232 and applied 12V to the power the board, the continuity between the pins was 0Ohm... (still ok?)>Then apply nominal power to the fscomm3 and try applying 12V>dc to pins 7 and 4 of the serial port connector, and check>that corresponding pins on the FSBUS connectors change from 5V>to zero.Here's what I did:-Power up the board using 12V-Reset the board using jumper-Jumper on pins to activate program mode-->Pin 1 and 2 to the FSBUS connectors are now both measured at 5V-Applied 12V to:-->Pin 4 of serialport connector: Pin 1 is 0V and Pin 2 is 5V (on FSBUS connectors)-->Pin 7 of serialport connector: Pin 1 is 5V and Pin2 is 0V (on FSBUS connector)Which seems ok.>This should ensure that everything is ok.>If that's the case, and your serial cable is ok...>I don't know what else to do :(>There MUST be something screwed to track down...Yeah there must be. :-mad And I'm gonna find out eventually :-madRoel.

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>BTW,>>Pin 10,11,12 >>what counting do you use?>>like this>>>16 15 14 13 12 11 10 9>1 2 3 4 5 6 7 8>(which it should be, I think)Looking at any chip with the serigraphy readable, and pins aligned horizontally, prcatically ALL chips have pin numbered in ccw starting from lower left.That's like you reported above.What you wrote below, and how you did the test is no use as you where testing other things.

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>First of all I used these pins:As i said above these are wrong:these are pins 13,14,15>Pin 12 - Is okay BUT gives 1500kOhm on the GND pin (I think>mainly caused by the N4148 diode at the bottom of the board>connecting it. This seems to be ok? When I reinserted the>MAX232 and applied 12V to the power the board, the continuity>between the pins was 0Ohm... (still ok?)It may well be.You are measuring pin13 which is the pin that commands the MCLR trasnsistor to give the 13,5v.It may well be that you pass through the junction of the transistor, thus reading conduction.>Here's what I did:>-Power up the board using 12V>-Reset the board using jumper>-Jumper on pins to activate program mode>>-->Pin 1 and 2 to the FSBUS connectors are now both measured>at 5V>>-Applied 12V to:>-->Pin 4 of serialport connector: Pin 1 is 0V and Pin 2 is 5V>(on FSBUS connectors)>-->Pin 7 of serialport connector: Pin 1 is 5V and Pin2 is 0V>(on FSBUS connector)>>Which seems ok.And in fact is.Hmmm...This is foundamental: if this works i dunno what else could not work.Have you tried another max232?Have you tried everything on another compupter?Try also measuring the output of the serial port, while changeing the troubleshooting in the software.When you see in the software 0V for data and/or clock and/or MCLR-reset, you should read 12V on pin 7 and/or 4 and/or 3 of the serial port.When you put eighter signal to 5V/13,5V the corresponding pin on the serial port should go to -12v.

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