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[solved]Just've finished the build,everything's working but LEDs...

nnbvehnnbveh
edited February 2014 in General
Hi guys,

as it say in the title, i've my box working, sound, sequencing, display, all seem to be fine, but there's no single LED is working. I don't have SD card with me right now so can't upgrade the firmware, and after checking other posts it doesn't look like the same kind of problem which other people had, or maybe i've missed something,sorry if it is covered already.

Any ideas on what to check and how? i went with multimeter through all the suspiciously looking solder points, nothing's wrong there, all the IC's are installed correctly, resistor networks also...

Thanks! 

Comments

  • fcd72fcd72
    Check all 595, 165 and 4051 chips - you may have scrambled some….
  • nnbvehnnbveh
    Just remembered that there was no 595's in stock, i've got these instead:

    http://se.mouser.com/ProductDetail/STMicroelectronics/M74HC4094B1R/?qs=sGAEpiMZZMtsbn1GaJyslxOUL8ggBi%2bRxjTjSCzABc8=

    they seem to be identical, but maybe they not...
  • julianjulian
    the 595 ICs are responsible for LED control.

    the HC4094, while being a serial in paralel out shift register, too, is not suitable here.
    I just had a look at the pinout in the datasheet, the functions are on different pin positions then on the 595

  • fcd72fcd72
    edited February 2014
    This is the 595 Pinout: image

    This is the 8574xx4094 Pinout: image

    As you might spot, besides the Positive Supply Voltage and the negative Supply Voltage (in case of the 595 its GND) these parts have nothing in common besides the fact they are 14 Pin DIL Chips. You can't substitute two chips just because the functional description says 8 Bit PISO, Shift Register its like buying a Screwdriver instead of a Bucket Wheel Excavator just because both are "Tools" 

    >-)

    You might have killed your 4094s btw…

    Solution: get some 74xx595s (anything will work for xx) and retry. 
  • nnbvehnnbveh
    haha, i like this screwdriver vs bucket wheel excavator comparison)) even though i think it might be a bit exaggerated,no?i maybe should've ask before order things stuff though) but i've compared the data, and they looked like the same thing basically...

    the thing is Mouser lists 595 as end of cycle or whatever it's called, so i've assumed they got replacement for it in a form of other part, haha)

    thanks for confirming this, gonna try to source proper IC's...
  • nnbvehnnbveh
    This is the 595 Pinout: image

    This is the 8574xx4094 Pinout: image

    As you might spot, besides the Positive Supply Voltage and the negative Supply Voltage (in case of the 595 its GND) these parts have nothing in common besides the fact they are 14 Pin DIL Chips. You can't substitute two chips just because the functional description says 8 Bit PISO, Shift Register its like buying a Screwdriver instead of a Bucket Wheel Excavator just because both are "Tools" 

    >-)

    You might have killed your 4094s btw…

    Solution: get some 74xx595s (anything will work for xx) and retry. 
    the thing is, if you copy data from 595's and compare it with the description of the ones i've ordered, on Mouser at least, they DO look identical indeed...i've learned something today, feels good, next time gonna check data sheets as well...

    but it is all very confusing, i'm as far from this industry as it gets, just want some nice drum machine)
  • fcd72fcd72
    Most Mouser EOL announcements are for that specific single Chip from that specific single vendor. A general EOL for 595 would be like the announcement tomorrow there will be no sugar anymore, anywhere. Just get any 595 from any manufacturer, they all will work.

    BTW EOL means something like "In 18 months we will stop production and then well sell out 144 40ft containers full of stock"
  • nnbvehnnbveh
    will these work? 

  • fcd72fcd72

    the thing is, if you copy data from 595's and compare it with the description of the ones i've ordered, on Mouser at least, they DO look identical indeed...i've learned something today, feels good, next time gonna check data sheets as well...

    but it is all very confusing, i'm as far from this industry as it gets, just want some nice drum machine)
    As pointed out above, you only compared the "TOOL" Part of the description. Not the "Weight: 1850 tons" vs "Weight 110g" or the "overal sIze 270m" vs "length 145mm" part. 

    Mouser provides a Datasheet for every component, if you would have had a look there you would have found out yourselves. Guess why there are different part Numbers - wouldn't make much sense if some parts would be exactly the same i guess….

    Bottom line: don't buy any part that looks somehow familiar ;-)
  • fcd72fcd72
    edited February 2014
    yeah they will work, but 4,90 of what Item? If its not italian Lira its way to much i guess.


    is the reasonable average price in €
  • nnbvehnnbveh
    haha, yes, i've missed the 'weight' part))

    no, it is not italian Lira, but swedish Krona, something similar)
  • nnbvehnnbveh
    updated firmware and the top row of LEDs is on now, weird, considering i've got totally wrong IC's...

    gonna get right ones next week, blinking lights...
  • nnbvehnnbveh
    have changed the IC's, all the LED's started to work, but after half an hour sequencer row stopped to light up when in voice mode...LED's are still working when i go to the step edit mode, so if i press one step it blinks.

    What could it be?

    Thanks!
  • mixrastamixrasta
    edited February 2014
    Maybe it's just normal if it already worked out. I'm new to the LXR and always wonder where I am, sometimes you have to shift and LED, sometimes I'm just in a blank pattern when in Pat/Gen. That means I wouldn't worry too fast after you saw the light ; ). Check the different modes or just reboot. Hope that solves it.
    I'm saying this because I thought I had some issues with soldering, but then just pressed the wrong knobs...
  • nnbvehnnbveh
    yes, my first thought was that i'm in some kind of mode where the lights should be off, but no, i'm in the step programming mode, and the step lights should go on or off when i turn on or off the steps, but they don't, not any more, even though for a first half an hour it worked perfectly)

    Guess some component blew up. Weird is that all those less are working in other modes, so i'm hoping that somebody who know how this thing organised would point me to which component is blown or something)

    thanks for answering
  • mixrastamixrasta
    Hope you solve that soon and be ready to start!
  • loderbastloderbast
    if they work in other modes, i don't think something is broken.
    seems like a softwaare issue to me. strange though - i am not aware of any knows issue or bug that caused behaviour like this.
    maybe try to refalsh the fw?
  • nnbvehnnbveh
    yes, i should try reflashing! thanks for the idea.
  • nnbvehnnbveh
    Re-flashing worked, now all LEDs are in order, thanks. I actually have that alternative firmware, maybe the bug is only in it,dunno.
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