sequencer crashes (and then some more questions)

MIDIbox SEQ
1

hi folks.

i finally got my sequencer up and running and i must say i’m quite pleased with it!

so far the good news :wink:

1: i was playing around with it yesterday, and after about an hour or so it crashed! by crashing i mean the thing shutting down, leaving all notes hanging.

it does work again when i restart it.. but then after about 15 minutes it goes again.

my 7805 (without heatsink) is getting really really hot, could it be it goes into thermal protection and shuts the system down?

also i have to say it’s not in any enclosure, i mounted everything onto a metal plate, wich balances onto two teacups.. :wink:

i guess the wiring is pretty vulnerable this way. is it possible that i shorted out something by accident and made it crash this way?

i didn’t actually touch any wires so i think it is pretty unlikely, but i thought i had to mention it to rule that out.

2: the ‘exit’ button doesn’t do anything. it is connected and working (midio128 tells me so anyway), so i’m wondering if it has no function on the application anymore as of an earlier update?

3: i’d like to get rid of my wall-adapter and replace it with an internal psu. wich is the minimum power at wich this should run? is it for instance a good idea to get my hands on a 5v trafo? will this for instance reduce the heat on the 7805? or does the 7805 require 9 volts. i’d be pleased if someone could give me the lowdown on this :slight_smile:

4: i think i need to heatsink my 7805, even if the crashes aren’t caused by it. will anything metallic with some cooling paste on it do as a heatsink? :slight_smile:

5: is it possible to make 32 (or longer) step patterns? if not, will this ever be possible? i think it would be very very usefull!

6: perhaps something for a future implementation; how about a second drum mode in wich you can specify 2 note values the same way you can specify 2 velocity values using the accents. i think it would enrich the drum mode a lot this way!

thanks!

2

hi,

your problem is cause you don’t have heatsink, you’re right.

is it possible to make 32 (or longer) step patterns? if not, will this ever be possible? i think it would be very very usefull!

it’s for the next uptdate (read the seq v3 wishlist)

3

I also think that this is because of a missing heatsink - the two LCD backlights make the 7805 really hot, sooner or later the voltage will drop much below 5V, and this resets the chip

Exit button: it should work, you will get into the menu

Drum mode: the future MBSID V2 will offer more possibilities, but I don’t plan to enhance the drum mode. Instead I’m planning a more general way to assign values to the layers, which makes the drum mode obsolete. (as Moxi has mentioned - check the wishlist -> http://www.ucapps.de/midibox_seq_v3_wishlist.html :slight_smile:

Best Regards, Thorsten.

4

thanks, gonna fix me a heatsink asap then :wink:

i didn’t see that list yet. looks very promising! :slight_smile: i might just wait with ordering my frontpanel till this is out :wink:

btw: any tips on that power supply? i really have no clue what transformer would be sufficient. (noob, you know :wink:

5

Hi,

btw: any tips on that power supply? i really have no clue what transformer would be sufficient. (noob, you know Wink

You can’t use a 5V transformer. The 7805 needs some volts more to regulate. It should be minimum 7V, better 9V. The transformer should deliver about 1A, better a lttle more (1,3 or 1,5A). The max current of the regulator is 1A.

Often forgotten.

Fuses for the transformer:

A fast blowing fuse primery and a fast or medium  blowing fuse secondary. The fuse values depend on the transformer.

This prevents your box (or your transformer) from dying, when something went wrong …

And also don’t forget: If your enclosure is out of metal you should’nt use a internal transformer if you don’t know exactly the safety rules for doing this.

If your case is out of metal … take the external transformer.It’s for your safety!

greets

Doc

6

hmm.. safety. that’s something i didn’t really think about yet. :slight_smile:

i guess the chance of electrocuting myself would be pretty big if i did this myself. someone i know is pretty skilled in electronics though. would it be smart if i let him fix this for me?

or is putting an internal psu inside a small case were everything is packed together on a tight space potentially unsmart?

7

i might just wait with ordering my frontpanel till this is out

No need -

I don’t want to throw away my existing case, therefore it can be considered, that MBSEQ V3 will run with the same hardware. New functions will be accessible from the menu and with special key combinations.

The next version should run fine with the same hardware, you just need to put in the new chip and maybe some minor mods.

Justin

8

Hi,

or is putting an internal psu inside a small case were everything is packed together on a tight space potentially unsmart?

No, it isn’t unsmart, but …

… if it’s a metal case (or a metal frontpanel): It’s dangerous. You have to pay attention to a couple of rules then. You have to take care that under no circumstance a life wire can touch the metal case or another part inside the box. You have to “earth” the box. And several others…

i guess the chance of electrocuting myself would be pretty big if i did this myself. someone i know is pretty skilled in electronics though. would it be smart if i let him fix this for me?

Yes, this would be smart!

Don’t forget. It’s fun building a midibox but it can kill you if you play around with main power , especially if you don’t know

what you are doinig…

greets

Doc