Manticore Posted May 3, 2009 Report Share Posted May 3, 2009 Hi everyone,I just put together a core module on breadboard (18f452 based) to use it for the Midimon application. Everything seemed to work fine: I've burned the bootloader to the PIC, then installed MIOS 1.9f and of course the Midimon V 2.0b. MIDI data on the Midi In are diplayed on the LCD. BUT: there is no function with the 4 buttons/switches. They are connected to J5, as shown in the diagram. However, there is no function if I press any of them. What is strange: the pins show nearly 0,0V even if no button is pressed; of course they are pulled up with a 8x10k Resistor array to +5V. Any ideas?Manticore Quote Link to comment Share on other sites More sharing options...
stryd_one Posted May 3, 2009 Report Share Posted May 3, 2009 You've hit the nail on the head - I'd be looking at the pullups with my meter... Where does the 5V become 0? Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 3, 2009 Author Report Share Posted May 3, 2009 I already did that: on the common pin of the array the 5V are present. 0V at the PIC pins. When I disconnect the resistor array from the pic pins, I measure +5V at the array pins.I did also try to replace the array with simple resistors; no effect. The array seems to be ok. I also replaced the 18f452 (might have been a damaged RA-port), but also no change in the behaviour.It seems that the pins are low by the software?! (I loaded the Midibox application from the ucapps site without any modifications).Very strange....Manticore Quote Link to comment Share on other sites More sharing options...
stryd_one Posted May 3, 2009 Report Share Posted May 3, 2009 It seems that the pins are low by the software?!Your description makes it sound that way... but the pins should be set as inputs... I'd be checking for software bugs but it's worked for everyone else so far, so hardware still seems the culprit. Are you able to show pics of your board? Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 3, 2009 Author Report Share Posted May 3, 2009 I put the whole d... thing on the flatbed scanner. Some components are hidden underneath the PIC (pull-ups and cap). The display is removed for the foto; it is plugged into the two male 16pin-connectors at the edges. The grey ribbon cable goes to the buttons. Red cables are +, black ones are ground. The yellow one goes to the luminance poti, the orange one connects the opto coupler with the PIC. Grey cables are miscellaneous connections (midi out etc.)Manticore Quote Link to comment Share on other sites More sharing options...
stryd_one Posted May 4, 2009 Report Share Posted May 4, 2009 I put the whole d... thing on the flatbed scanner. Well I have to say, that's a really effective way to get nice high-res shots of your pcb! Unfortunately I'm still not sure what's going wrong, but I'll try to help :)Some components are hidden underneath the PIC (pull-ups and cap).Err, darn... that r-net is what I was hoping to look at... How is it connected? I don't see any adjacent connections on the PCB under where the grey wires are, so I guess it's soldered direct to the PIC socket? Whichever way, this test:When I disconnect the resistor array from the pic pins, I measure +5V at the array pins.Should be viewed as having suspect results because there is certainly more than one change involved between tests (remove pic, desolder 4 joints, replace pic: that's 6 changes). Maybe no big deal, but worth noting...I notice you were a bit liberal with the solder... Even at such high res and zoomed into 200% I was not completely sure that the button joints didn't short each other. I didn't really look at the rest of the board but it's definitely a haven for shorts, what with the veroboard and unshielded wires and extra solder combined.. It might be worth using some braid or something to take some of that solder out of the equation....I'm not sure... :( Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 4, 2009 Author Report Share Posted May 4, 2009 Hmmm...I built a complete Midibox SID that way (at least the control section). By the way, I tested all connections and even possible intersections.The r-net is next to the PIC socket. When you look at the soldering side, pin 1 of the PIC is bottom left. R-Net pins are directly connected to the appropriate pic pins (2,3,4,5,7,8,9,10).In the mean time I tried something else: I put the pic in one of the pcbs of the SIDBox. To make it short: same behaviour even there! RA pins are 0Volt! Next thing I will check is a third PIC - it MUST be a hardware defect! Quote Link to comment Share on other sites More sharing options...
stryd_one Posted May 4, 2009 Report Share Posted May 4, 2009 Every so often, the replacement part has the same fault.... Good luck!(Are you following proper antistatic procedures while handling these?) Quote Link to comment Share on other sites More sharing options...
TK. Posted May 4, 2009 Report Share Posted May 4, 2009 Hi,could you please try this updated release: http://www.ucapps.de/mios/midimon_v2_0c.zipI noticed that v2_0b contained an expired J5_IO driver, which got some changes meanwhile. This could be the reason.Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 4, 2009 Author Report Share Posted May 4, 2009 Hi Thorsten,cool...the boss himself is taking care of my problem :D.Thanx a lot; I'll try it tomorrow morning and will post my results.Manticore Quote Link to comment Share on other sites More sharing options...
stryd_one Posted May 4, 2009 Report Share Posted May 4, 2009 Hah, that explains a bit... I was looking at the code in SVN (which is the 2.0c version), not in the zip file.... ooops!! Sorry!! Quote Link to comment Share on other sites More sharing options...
Manticore Posted May 9, 2009 Author Report Share Posted May 9, 2009 Unfortunately it took some days before I found the time to check the updated firmware, but now I can say: it works now! Thanx for the supply to stryd_one and of course to Thorsten!Walter a.k.a. Manticore Quote Link to comment Share on other sites More sharing options...
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