tel3 Posted April 18, 2006 Report Share Posted April 18, 2006 OK, So I just finished my first CORE R4C module and attempted to test the voltages on the IC socket pins as described on the CORE page...I seem to only be able to get about 1.41v on all of the pins described for testing the CORE. I get the same voltage just about everywhere else on the board that is supposed output 5v too. There is one thing that may be the culprit but I am not sure. I know it was probably not the right way to test but, I was not testing with the PSU, I was using a 3 "D" battery pack. Should that matter? I should still get at least 4.00 volts right? I get 4.46v directly from the battery pack.Someone please just tell me it was because of the battery pack, and not something wrong with my beloved CORE module!! :)-tel3 Quote Link to comment Share on other sites More sharing options...
drin Posted April 18, 2006 Report Share Posted April 18, 2006 There is one thing that may be the culprit but I am not sure. I know it was probably not the right way to test but, I was not testing with the PSU, I was using a 3 "D" battery pack. Should that matter? I should still get at least 4.00 volts right? I get 4.46v directly from the battery pack.Someone please just tell me it was because of the battery pack, and not something wrong with my beloved CORE module!! :)I can't tell you that for sure, but it's quite possible. If you've populated the 7805 voltage regulator on the core but you're feeding it less voltage than it requires to function correctly your core voltages will be all messed up. I believe a 7805 requires at least two volts above its regulated 5V output to function correctly. Feeding it anything less than 7 volts will result in weird voltages all across the board. 4.46V simply ain't going to cut it.-drin Quote Link to comment Share on other sites More sharing options...
tel3 Posted April 18, 2006 Author Report Share Posted April 18, 2006 Alright, I'm gonna hook up the PSU like I should have...That was a dumb idea!-tel3 Quote Link to comment Share on other sites More sharing options...
tel3 Posted April 18, 2006 Author Report Share Posted April 18, 2006 Is It necessary to connect the cap and diode like in the sid_c64_psu.pdf schematic in order to just test the CORE? I don't think I have those parts yet!-tel3 Quote Link to comment Share on other sites More sharing options...
drin Posted April 18, 2006 Report Share Posted April 18, 2006 Is It necessary to connect the cap and diode like in the sid_c64_psu.pdf schematic in order to just test the CORE? I don't think I have those parts yet!That depends. You haven't said what PSU you're using.-drin Quote Link to comment Share on other sites More sharing options...
tel3 Posted April 18, 2006 Author Report Share Posted April 18, 2006 I'm using the c64 PSU. I tried it anyway...I get 4.70v That's normal right? The lower voltage than 5v could be a result of my crappy DMM...-tele Quote Link to comment Share on other sites More sharing options...
tel3 Posted April 19, 2006 Author Report Share Posted April 19, 2006 I STILL CAN'T GET IT TO WORK!!! >:(Sorry, this can be frustrating though! Somebody has to know what is up with my core? (and how to fix it!) So here's the deal so far...I tested the socket pins originally before inserting the ICs. The voltage was at like 4.70v. Then I realized that my DMM was not giving me correct readings and was somewhat busted, so I figured everything was a go after testing with a better DMM. Then I attempted to upload MIOS via MIOS Studio. I could not get it to work correctly (upload) after several tries. So I checked everything and then rechecked everything to make sure there was nothing wrong with my solder joints, PSU connections, etc. and...just my luck, STILL NOTHING! ??? Then I tried measuring the core Vdd as described in the MIDI interface troubleshooting pages. I can't seem to get 5v on one of the pins/points described! I don't get it! I am able to get 5.10v on many other pins! Oh yeah I almost forgot, my core IS sending the "Upload Request" message to the computer too...But, will not seem to upload MIOS no matter what I do!!! I assume it has something to do with my voltages not being there on the points to be tested while measuring the cores Vdd, and being just about everywhere else? Maybe a short? Maybe a cap or diode installed incorrectly? I don't think so...I'm just hoping it's that simple!So what do you guys think? I'm puzzled ???-tel3 Quote Link to comment Share on other sites More sharing options...
raphael Posted April 19, 2006 Report Share Posted April 19, 2006 I can't seem to get 5v on one of the pins/points described! I don't get it! I am able to get 5.10v on many other pins! What pin is it then? And what pins are the "many other" pins? Or is this a quiz?Have you already done all the tests from the troubleshooting page regarding a not working MIDI-IN? (As you describe you`re MIDI OUT seems to be ok.) Quote Link to comment Share on other sites More sharing options...
tel3 Posted April 19, 2006 Author Report Share Posted April 19, 2006 Hey Raphael, Thanks for your interest in helping!I guess I should have clarified better...Sorry! Well anyway, I actually meant not one of the pins described for testing can I get a voltage reading! And, the "many other" pins are various pins on the PIC and a few on the 6N138 Optocoupler, also on the J2 Vd point is a normal 5v or so, as well as all the other Vd's on the board are 5v as normal. When I get home after my N.Y. trip I can re-test and list the exact pins that do give the normal reading, and the pins that don't. ;) I don't think I have done much of the MIDI in tests, but I still should be getting 5v on the PIC and Opto's pins as described on the MIDI troubleshooting's measuring Vd page right? -tel3 Quote Link to comment Share on other sites More sharing options...
raphael Posted April 20, 2006 Report Share Posted April 20, 2006 I don't think I have done much of the MIDI in tests, but I still should be getting 5v on the PIC and Opto's pins as described on the MIDI troubleshooting's measuring Vd page right? Yes, first things to check are correct Vd and ground connection:http://www.ucapps.de/howtodebug/mbhp_core_extract_measuring_vdd.gifhttp://www.ucapps.de/howtodebug/mbhp_core_extract_measuring_gnd.gifSo it would be helpful if you can give us the exact readings.Raphael Quote Link to comment Share on other sites More sharing options...
tel3 Posted April 21, 2006 Author Report Share Posted April 21, 2006 Cool, Thanks Raphael! I'm In Brooklyn, NY right now for the BENT circuit bending festival over in lower Manhattan right now, so I'll do that as soon as I get back home to B-more!_tel3 Quote Link to comment Share on other sites More sharing options...
illogik Posted April 22, 2006 Report Share Posted April 22, 2006 hey;it's best that if you don't have the right voltages at the pic socket; you pull the pic out, and first get these voltages right. If you say you have 5 volts on some points but not at the pic i'm almost sure that you have some bad solder connections.if it's the psu your worried about, you could try power the core with a wall wart/adapter which delivers anything between 7-10 volts, 500mA (if you have no lcd can be less also), this is for me always the easiest way to get the core workingcheers, marcel Quote Link to comment Share on other sites More sharing options...
tel3 Posted April 22, 2006 Author Report Share Posted April 22, 2006 Hello Marcel, it's best that if you don't have the right voltages at the pic socket; you pull the pic out, and first get these voltages right. Yeah I was afraid someone would say that! Getting those DIL40's out are a pain when you don't have an IC pulling tool!f it's the psu your worried about, you could try power the core with a wall wart/adapter which delivers anything between 7-10 volts, 500mA (if you have no lcd can be less also), this is for me always the easiest way to get the core workingAbout the PSU, I have tried a few different ones. Even a 9v battery! ;DThanks for the help, Much appreciated! _tel3 Quote Link to comment Share on other sites More sharing options...
illogik Posted April 22, 2006 Report Share Posted April 22, 2006 Yeah I was afraid someone would say that! Getting those DIL40's out are a pain when you don't have an IC pulling tool!if you have one of those really small&flat screwdrivers, you can get the PIC out by gently pushing the screwdriver between PIC and it's socket.cheers, marcel Quote Link to comment Share on other sites More sharing options...
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