www.megadrum.info

I purchased a MegaDrum kit form Dmitri. I am in the middle of reworking my MegaDrum and adding a bigger color LCD. In the process a few wires pulled out of the PCB board for the button and encoders. As I was looking at it I wondered if I could forget about them. I never use the button or encoders. I use MDM only. I have done some looking on the forum and older posts say that you need the bottom button to do firmware updates. Is this still true? I have used MDM many times to update the firmware without using a button. I just want to make sure that I am not missing something. Thanks.

In case of an interrupted/failed firmware upgrade you must be able to use LEFT button to force MegaDrum into bootloader mode. Everything else can be done from MDM.

I decided to just add the left button. I did some research and concluded that you couldn't do that. (correct me if I am wrong) So I purchased 4 momentary switches which are "normally open - NO" (only complete|short the circuit when the button is pushed). I connected them and they don't seem to work. I followed the attached schematic. I have the MegaDrum STM32 ver.3 board. I know that diodes are directional and the black line is the negative side. Any suggestions?

Stephen Spurlock wrote:I decided to just add the left button. I did some research and concluded that you couldn't do that. (correct me if I am wrong)

Yes, you are wrong, you can add just one button?

So I purchased 4 momentary switches which are "normally open - NO" (only complete|short the circuit when the button is pushed). I connected them and they don't seem to work. I followed the attached schematic. I have the MegaDrum STM32 ver.3 board. I know that diodes are directional and the black line is the negative side. Any suggestions?

Broken buttons?

Ok, I misunderstood the post on: http://www.megadrum.info/forums/viewtopic.php?f=3&t=2638&start=10
___________________________________________________________
dmitri wrote:
Just the button LEFT is needed for this.

airflamesred:
Yes, only the LEFT button is needed, though you will have to do a considerable amount of work to separate that button out.

Can I request that the 'auto resize' be savable as part of the mds?
____________________________________________________________


Anyway, going forward with my four buttons that I have now purchased.

I have checked the buttons with my multimeter on the continuity setting. When the button is pushed there is a short circuit. I based how I read the schematic for the diode off the attached image. Is that the correct direction for the diode?

Since I am not using any encoders I just leave the "encoders" pin headers empty right?

I am not really sure what could go wrong.

The LEFT button connects to the board without diodes.

Ok. I will rework it tomorrow and just have one button to see if that works. I will let you know.