Digital OutPut problem

[Hood]

I am hoping Boris or someone else can shed some light on this. I have a video uploaded to youtube if you click on the link you will see it.
 I am using a digital output to power a pot for an analogue input.
What happens is I connect the USB and go into the PoKeys software and connect, I look at the analogue  input and as you will see with the pot turned up full there is less than  a 1/4 of the bar showing. I exit the analogue tools page and  without doing anything else I press Send to Device, I then look and the analogue is fine. I close the software, unplug USB, Plug USB back in and have to go through the same procedure again to get the digital output powering the analogue input properly. When its working the digital OutPut is putting out the correct 3.3v but when its not then its only putting out 0.6v.

Hood

http://www.youtube.com/watch?v=fd-ZMVyVddU

[borisz]

Hi!

Do not use digital output to power the pot.
There is 3.3V on the board on the biggest šad of 1117 voltage stabilizer on the first release (PoKeys55)
On the new PoKeys55 boards you have 3,V on the connectors

regards

Boris

[Hood]

I think I must have the first release as none of my connectors are marked for power out. Can you please explain where I can get the 3.3v from as I am unsure what you mean by "biggest šad of 1117 voltage stabilizer"

Hood

[borisz]

Look at the picture.

regards

Boris

[Hood]

OK thanks.

Hood

[budman68]

So Hood, you're going to solder a wire to one of those 3.3v legs on the chip in the pic and one to ground on the board and then another one to one of the pins on the board?

Dave

[Hood]

Nope,  what I have done is  superglued a double terminal screw connector  to the side of the USB housing and soldered the legs of it to the chip, it partially hides the power LED but I dont care That way I can connect a few wires into the 3v later on if required. I dont need to solder the ground wire as there are terminals for ground on each block of 11 I/O connectors.

 I am still a bit worried why the Digital output keeps turning itself partially off after the USB is unplugged/replugged,  but have not tested setting up as an actual output in Mach yet to see if it does still do that.

Hood

[budman68]

Cool, thanks for keeping us (me) informed - 

Dave

[Hood]

Heres a pic of it, the solder legs of the terminal block are bent down and both soldered to the chip, allows me to have a few 3.3v wires if needed for more pots etc.
 I was getting noise picked up in the pokeys, thought it was probably because I didnt have the shield earthed yesterday as I am just testing. Today I wired it to earth and still was picking up the noise so presumed it was the pokeys itself picking it up. As a test I just joined the shield wire into the Gnd terminal on the pokeys and the problem has gone. When I actually install it in a machine it will be properly earthed to the star point to avoid a loop but this at least let me know it cures the problem.

Hood

[budman68]

Excellent, good for you and thank you for the picture - 

Just to clarify, each lug that Boris pointed out in the above pic is 3.3V, correct? And then as you mentioned that you took the lugs from your black screw terminal and soldered those directly to the lugs on the chip making it now possible for you to just connect any 2 things that requires 3.3V to your screw lug terminals. Do I have that right? It's like adding even more outputs...lol

Dave