hexman Posted October 8, 2006 Report Share Posted October 8, 2006 I have my CORE assembled and have problems loading the mios_v1_9c_pic18f452.hex - actually it doesnt look like the core is sending midi ready messages out. I have a pic and core from SMASHTV with the 1.2 v bootloader (all 00000's).All +5V check out fine, all ground check out fine, diode is correct, crystal is installed. Midi IN/OUT on my computer and the MIOS Studio is working as verified with my midi keyboard. All solder joints look good. Using the midi connectors that mount right to the board so should be no wiring mistakes to plugs etc. All resistorv values are correct.I do not get any midi messages comming into the MIOS Studio from my CORE. Nothing. I just have the core hooked up - do I need to ground any pins or have a DIN module connected? LCD connected or not doesnt seem to change anything.What is "TEST PROG1: If you are not sure that the bootstrap loader has been burned successfully, use the verify function of IC-Prog/P18" ??? How do I do this?What can I do next???--2:30--Update - btw, the display when plugged in just has ########### is this normal? Backlight is working. But of course no change w or w/o the display connected.Maybe this is something ???Also - the TX (pin 25) from the PIC is measuring 0.5 V all the time. The troubleshooting instructions say this should be "5 V when nothing is sent" - clues ??? Quote Link to comment Share on other sites More sharing options...
TK. Posted October 8, 2006 Report Share Posted October 8, 2006 I would propose to disconnect all modules to reduce the number of possible errors, use only the core module for the first upload test, even the LCD should not be connected (yes, the black bar is normal so long MIOS hasn't been uploaded)Pin 25=0.5V: sounds like the PIC is not running, or that there is a short between the Tx track and another trackBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
hexman Posted October 8, 2006 Author Report Share Posted October 8, 2006 I have run the core completly alone w/o any other module with same results.sounds like the PIC is not runningCould this mean no bootloader is installed? What is verify function of IC-Prog/P18 ? Quote Link to comment Share on other sites More sharing options...
TK. Posted October 8, 2006 Report Share Posted October 8, 2006 press the "compare PIC with Hex File" buttonBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
hexman Posted October 8, 2006 Author Report Share Posted October 8, 2006 press the "compare PIC with Hex File" buttonok - so I'm an idiot but HUH?I did look at the path from the midi i/o connector to the TX pin and its 220 (just the resistor resistance) and >4meg to ground. Quote Link to comment Share on other sites More sharing options...
TK. Posted October 8, 2006 Report Share Posted October 8, 2006 What is the resistance to other tracks which are routed close to the Tx signal?Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
hexman Posted October 8, 2006 Author Report Share Posted October 8, 2006 they're all about 4.6 meg ohmsBTW - thanks for the quick reply and all the help so far. I'm sure we'll get it sorted... Quote Link to comment Share on other sites More sharing options...
TK. Posted October 8, 2006 Report Share Posted October 8, 2006 So, the first option seems to be true: the PIC is not running...Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
hexman Posted October 8, 2006 Author Report Share Posted October 8, 2006 by PIC not running - do you mean it may not have a bootloader or physically damaged?? or could be either??? Quote Link to comment Share on other sites More sharing options...
TK. Posted October 8, 2006 Report Share Posted October 8, 2006 I really don't know, my only hope is that you find out a detail sooner or later which really helps somebody to determine the reason. Just remind, that some of us guys are sitting 1000tes of miles away and cannot look over your shoulder.Or would you prefer that I say "the PIC is damaged, buy a new one", although the reason is just that there is a small invisible soldering clump between MCLR# and Vss which resets the PIC permanently? (just read this troubleshooting section and you will know what I mean)Which voltages do you measure on the other pins of the PIC (measured against ground).Maybe this gives a hint...Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
hexman Posted October 8, 2006 Author Report Share Posted October 8, 2006 I plan on looking at the whole thing tomorrow under 7x-15x microscope to check solder joints etc.I plan on tracing ALL the tracks etc to make sure of the connections.Im only trying to understand the possible causes of the low TX - if it could be a bootloader thing then I wont find anything until I either get another one from SMASHTV or have him check no matter how hard I look. Hence my question if it COULD be a bootloader issue.Thanks for your help. Quote Link to comment Share on other sites More sharing options...
TK. Posted October 8, 2006 Report Share Posted October 8, 2006 Of course, it could, but the propability is very low, because this never happened in the last 4 years. Nethertheless, just 10 minutes before your last posting I asked him via PM to doublecheck this, since somebody else had a similar issue. Hope that this tell you, that we don't ignore such issues (we would even not ignore them if you would avoid to WRITE IN THOSE AGGRESSIVE CAPITAL LETTERS!)However, please measure the voltages of all PIC pins, maybe it allows me to determine a possible error immediately, maybe not... but it's worth the effort (especially because I've not so much time for supporting people in the next week until next monday - somebody else must help)Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
hexman Posted October 8, 2006 Author Report Share Posted October 8, 2006 Thanks and i PROMISE not to use caps!!I just checked all voltages on the PIC. Except for the pins that are specified to have either 5v or 0 (ground) as called out in the troubleshooting guide they all measure approx 0.75 v (including the TX pin). I checked this on the PIC not the pcb to make sure I was getting real voltage at the pic.I checked ohms between each pic pin (on the PIC not the pcb) and the resistance is 4 or greather meg ohms between each pin (should be no connected solder blobs between pins).Hope this helps... I really do appreciate the help. Quote Link to comment Share on other sites More sharing options...
TK. Posted October 8, 2006 Report Share Posted October 8, 2006 Ok, the only discrepancy I found is, that you haven't mentioned, that pin RC3 should have 5V although it's not mentioned explicitely in the troubleshooting guide. But I guess that all IO pins are in high impedance state, which proves again: the PIC is not running.Do you know how to measure the current drain? I don't have a special schematic for this, but maybe it's already clear to you... it could be measured at J1 (split one wire if required).Which value do you measure with and without the PIC? I don't know the exact value by myself, but if the current drain is much higher than 1 mA, I would say the PIC is running, but no code is started (this still doesn't mean that the bootloader doesn't exist in flash). If it is less than 1 mA, the propability is high that there is an issue with the crystal or the 33 pF capsBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
hexman Posted October 8, 2006 Author Report Share Posted October 8, 2006 Not shure if this is right for "current drain" but I measured voltage across a 10 ohm resistor in one of the power transformer lines to J1 and have about 90 mV AC across the 10ohm resistor (Im using an AC power supply to the bridge) - so I'm getting about 9 mA (minus convert to dc). I'll pulled the pic and its 75mv across the 10 ohms (7.5 mA).Sorry - I made a mistake in my original report. RC3 (pin 18) is indeed 5 v as is RA4 (pin 6), RD5 (pin 28) as well as the specified in the trouble shooting (mclr pin1, vdd pin 11, RD1 pin 20, RX pin 26, vdd pin 32). VSS is 0V But TX pin 25 is indeed about 0.8VMatt Quote Link to comment Share on other sites More sharing options...
TK. Posted October 9, 2006 Report Share Posted October 9, 2006 I just realized that this is a brilliant test to get a feeling, if the bootloader is started or not (again: it doesn't mean if the bootloader is flashed or not). Note that you don't need to take a resistor if your multimeter provides an ampere measuring mode (which is mostly the case).So, here some values:without PIC: ca. 7.5 mAwith PIC, bootloader running: 25 mA, a short peak of ca. 30 mA after two seconds (MIOS init phase)with PIC, MCLR# reset permanently active (connected with ground): more than 50 mA !with PIC, but without crystal: 9 mAwith "virgin" PIC (not flashed) - the same as without crystal: 9 mA, propably because the oscillator mode is not configuredI found it very interesting, that your results are matching with mine. But at the end it doesn't help you so much, because they just confirm that it's very likely the crystal (or the 33 pF caps), or maybe (with a very low propability) a missing bootloader. Has Smash already contacted you?Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
hexman Posted October 9, 2006 Author Report Share Posted October 9, 2006 Interesting - based on you readings I am suspecting the caps or crystal as well. Is there any way to directly check the crystal - I have access to a o-scope if required.Smash has indeed contacted me and made a more than generous offer to assist with troubleshooting. I think I will take him up on his offer unless I can verify the crystal.BTW- I did get a chance to look at all the solder joints under 7-15x microscope and they all looked fine. No lifted pads or breaks either. Quote Link to comment Share on other sites More sharing options...
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