Unable to update software

[jmcdougall]

I finally put my megadrum together -- Based on the Synthex 2.7 board. I purchased a new CPU from Dimitri with the protected bootloader. Once everything was together I started testing and it basically works but was running into weird false trigger based on note 63. Found a post that indicated this had been from a version problem between the CPU and the PIC so I realized I neede to download the new firmware to get everything in sync.

Downloaded MDUpdate.exe dated 6/24/2010 which is the version from the downloads page

also downloaded and unzipped megadrum_20110816.zip to get megadrum644_56_20110816.bin

Start the megadrum as per instructions so that it is in the StartUpdateonPC status
after selecting 20MH

Start MDUpdate.exe and select the Midisport IN and Out ports and select browse and select the megadrum644_56_20110816.bin
file

I get the Updating Megadrum, please wait miniscreen and nothing happens for a while -- I can see no activity on the midisport midi led indicators.

Finally I get the following error display on the PC

Invalid checksum received, file is damaged

Same problem whether on my Vista PC or a Win7 laptop.

I know the midi ports are functional because MDM works OK

Where do I go from here ???

Thanks

Jim

[dmitri]

MIDIsport may not pass through all the messages required for the firmware update. Update firmware over USB.

[jmcdougall]

Wired in a USB port to the board via the 4 pin header. Plugged it into a WIn7 laptop and the device drivers installed properly. System sees the Megadrum.

Boot the megadrum and get it to the StartUpdateOnPC prompt

Load MDupdate and it shows Megadrum USB for both input and output. Browse and select the bin file noted above. The update prompt appears and one of two things happened:

It hung and nothing happened or about 1 sec in Medagrum rebooted. After thinking about problem I figured the PIC might be the problem and decide to pull and re-seat the chip. When I pulled it I found that one pin had folded in during the original insertion. Straightened the pins and re-inserted. Tried again with same result.

Something is preventing the download from starting. ??

Where to from here ?

[jmcdougall]

After i posted the last message, I decided to go back and try the midi interface since it was less dependent on the PIC. This time it worked ! Major improvement in false triggering problem - no more continuous midi stream of note 63.

However I have a dumb question. The suggested TRS jacks are shorting jacks so tip and ring get shorted to ground if you wire the shorting contacts to ground, which is what I did. For most CPU boards this is a typical way of doing things but I am wondering if this applied to Megadrum. If an input is unused , should tip and ring be left floating or should they be grounded ??

Thanks !

[kupooglop]

The suggested TRS jacks are shorting jacks so tip and ring get shorted to ground if you wire the shorting contacts to ground, which is what I did. For most CPU boards this is a typical way of doing things but I am wondering if this applied to Megadrum. If an input is unused , should tip and ring be left floating or should they be grounded ??

Are you talking about grounding unused megadrum inputs on the pcb or are you using a dummy jack that has tip and ring shorted to sleeve/ground? I don't know what you mean by "suggested". Is that from the synthex instructions? In my opinion, I would not modify the trs jack wiring on the pcb from it's original design. As far as my personal experience goes, the way I handle unused inputs is to leave them alone with nothing plugged into them. I have had no problems with this. And for an input that I only use half of, I use a tip-sleeve plug and set the notes to the unused channel to zero. Using a tip-ring-sleeve where the ring is open causes false triggers on that channel even with the notes set to zero. You could probably put a resistor across that channel but I have never tried. Using a mono (tip/sleeve) jack & setting unused channel notes to zero works fine. At least for me.

[dmitri]

You don't have to ground unused inputs.