Manticore Posted May 14, 2009 Report Share Posted May 14, 2009 I finally finished the MTC display for the Midimon. However, something's going wrong with it. If you look at the photo you see that the display shows really weird things.Of course I did some tests to find the fault, but no results were found:1. I triplechecked all connections and possible intercourses with my meter.2. I exchanged the HC595.3. I took the HC595s off the sockets, applied +5V to the anode pins and grounded the segment pins to check if all connections are o.k. All the segments were lit as they should.What is also strange is that the displays do not have the same brightness (as seen on the photo; display No. 7 is the brightest one). Even if I exchange them (they are mounted in sockets) the difference in brightness remains.Could this be another software bug in the Midimon app?ManticoreIMG_0003.JPGIMG_0003.JPG Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 14, 2009 Author Report Share Posted May 14, 2009 oh...I forgot to mention: when there is no time code displayed on the LCD, on the MTC display all segments are lit with the exception of segment f (the upper left one), including the decimal points.Manticore Quote Link to comment Share on other sites More sharing options...
nILS Posted May 14, 2009 Report Share Posted May 14, 2009 That doesn't look like a software bug ;) Can you take some pics of the wiring? Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 14, 2009 Author Report Share Posted May 14, 2009 ok...here they are. Maybe the wiring does not look that nice, but as I already said I did check it with the meter. Segment wiring is done with Vero-wire; orange wires are anodes, black is ground, red is +5V, white is SO, yellow is SendClock and violet is ReceiveClock. Connection to the Midimon goes via ribbon cable; this was also checked with meter.Manticore Quote Link to comment Share on other sites More sharing options...
stryd_one Posted May 15, 2009 Report Share Posted May 15, 2009 That doesn't look like a software bugI couldn't tell... IMG_0003.JPG (830.8 KB, 2272x1704 - viewed 112 times.) Scrolls riiiight off the side of the screen. If you go much more high res, we will be able to check the PIC's silicon die for errors ;) Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 15, 2009 Author Report Share Posted May 15, 2009 har har... :DI did notice that, too. Therefore I reduced resolution for the following pics. Sorry for the waste of bandwith :PHowever, you can at least check EVERY pixel of that LCD ;)To get serious: I think I will put the whole display together once again, but with a bit more accuracy. Maybe this could help...Manticore Quote Link to comment Share on other sites More sharing options...
stryd_one Posted May 15, 2009 Report Share Posted May 15, 2009 Therefore I reduced resolution for the following pics. Sorry for the waste of bandwith :PDon't sweat it bro, I'm just makin' a joke :) No point in my helping you out here, nILS knows what he's doing (in a big way!) so I thought I'd have some fun. Sorry to interrupt :/ Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 16, 2009 Author Report Share Posted May 16, 2009 Hi,now it works! After assembling another mtc board the fault was exactly present as before. But then after checking the midimon I found the source: it was the socket for the mtc display (sub-d 9 pin male). There was a connection where there should be none...However, one thing remains: as you see on the photo, decimal points are not at the correct position. What is this?!Manticore Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 17, 2009 Author Report Share Posted May 17, 2009 Oops...my own fault! The displays are with decimal point on the left, not on the right.Would it be possible to modify the software?Manticore Quote Link to comment Share on other sites More sharing options...
ssp Posted May 17, 2009 Report Share Posted May 17, 2009 hey manticore, good to see your getting things done!! im in the middle of finishing mine, not much more to do then its just doing the casework. i cant help regarding the software, but just xhange the pin wiring on the decimals one to the other, as yours has one each side of each segment display by the looks of it.seeing yours makes me a little itchy to get mine finished , but i have to finish the gm5 midi module thats going to control it first!once its all runnig and tested i can then get the casework done.its nice for me to see another one built and done! ssp Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 17, 2009 Author Report Share Posted May 17, 2009 Hi ssp,good luck for your housing; this mostly takes more time than the electronic side of a project. :(Unfortunately the displays do not have two decimal points. It is a HP 3730 type; there is also a version with the dp on the right and they seem to use the same housing for both types. I studied the datasheet AND tried all pins - no dp on the right :(Either I will have to live with this or must get some HP 3733 with dp on the right hand side. We will see...Manticore Quote Link to comment Share on other sites More sharing options...
ssp Posted May 17, 2009 Report Share Posted May 17, 2009 its just on the mtc front jpg on the top of the thread, it looks like there is two decimal lights per led. do you see what i mean?to be honest it wouldnt take you long to change the units out for replacements if you need to. Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 17, 2009 Author Report Share Posted May 17, 2009 yes, I know what you mean; however, only the left of the two decimal points has a LED inside, that's what I meant. The right "point" is only used in the 3733 display. Quote Link to comment Share on other sites More sharing options...
stryd_one Posted May 29, 2009 Report Share Posted May 29, 2009 You could fix it in software, just search for LEDDIGITS to find appropriate code; but it's much easier to rewire it ;) Quote Link to comment Share on other sites More sharing options...
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