how can I know if my mac is truly communicating with the MD?

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Re: how can I know if my mac is truly communicating with the MD?

Postby dmitri » Fri Feb 06, 2009 1:13 am

jeffbeckib wrote:BTW, I'm sure I'm not going to be the only Non technician trying to build this thing, and there is absolutely NO documentation on assembling this thing. Much of our interaction could probably have been avoided with step by step instructions. I know I may seem ignorant when it comes to basic electrical skills, but I have tackled far more difficult DIY tasks than this with less bumps. I'm no car mechanic, but with proper documentation I was able to practically rebuild my entire engine on my bmw. With your kit, I got a box with components and that was it. I couldn't find a single piece of documentation on your site. All the documentation you sent me about what resistor to use for the lcd, and any other helpful documentation was spread out all over the place on your site. I can't stress enough how although I don't have any experience with building electronics like this, that with the proper instructions, and basic soldering skills, this should have been a piece of cake, but instead I'm now regretting having gone this route.

I was trying to help. Apparently I must admit that I've failed in your case. My tutor's skills are not up to the task. I must agree with you that my documentation requires certain level of electronics knowledge. I will put a warning in huge block letters on the website about this. Sorry I let you down.


Do you not sell these already assembled??? so I could have just stuck it in a case and be done with it?

Because MegaDrum is for non-commercial use only.
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Re: how can I know if my mac is truly communicating with the MD?

Postby jeffbeckib » Fri Feb 06, 2009 7:15 am

I'm so sorry, you are correct. I have the wrong pins circled... Jesus...
Pin 28 Is however the pin I'm talking about. You can see the copper between that pin and the resister right next to it...
I'm sorry, I'm getting a little punch drunk juggling this project and being on vacation at the same time.


Synthex wrote:The pin on your photo is pin 31.
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Re: how can I know if my mac is truly communicating with the MD?

Postby dmitri » Fri Feb 06, 2009 3:39 pm

1. Replace the incorrect button.
2. Read this thread all over again.
3. Follow all advices I gave you in this thread.
4. Make all measurements I told you to do in this thread.

Come back with all your results.
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Re: how can I know if my mac is truly communicating with the MD?

Postby jeffbeckib » Fri Feb 06, 2009 5:54 pm

dmitri wrote:1. Replace the incorrect button.
2. Read this thread all over again.
3. Follow all advices I gave you in this thread.
4. Make all measurements I told you to do in this thread.

Come back with all your results.




will do my best
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Re: how can I know if my mac is truly communicating with the MD?

Postby jeffbeckib » Fri Feb 06, 2009 11:04 pm

Update. Since re-connecting the pic icu, my macbook now recognized the MD under the system profiler. Although I'm still not getting any display, this must be a sign of improvement. lol I'm also now seeing "megadrum midi usb" under the "configure options" page in MCT. Things are starting to look better. Is there anything I can utilize from the MCT to try and bring this thing back to life? or should I still keep checking everything else?
I tried doing a firmware update, but I'm not seeing anything happen.
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Re: how can I know if my mac is truly communicating with the MD?

Postby dmitri » Fri Feb 06, 2009 11:10 pm

jeffbeckib wrote:Update. Since re-connecting the pic icu, my macbook now recognized the MD under the system profiler. Although I'm still not getting any display, this must be a sign of improvement. lol I'm also now seeing "megadrum midi usb" under the "configure options" page in MCT. Things are starting to look better. Is there anything I can utilize from the MCT to try and bring this thing back to life?

No

or should I still keep checking everything else?

Yes

I tried doing a firmware update, but I'm not seeing anything happen.

Go on as advised.
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Re: how can I know if my mac is truly communicating with the MD?

Postby jeffbeckib » Sat Feb 07, 2009 3:30 pm

voltage

LCD
pin 2 = 4.87
pin 3 = 2.8

Pic18f2550
pin 14 = 4.87
pin 20 = 3.35

atmega32
pin 9 = 4.7
pin 10 = 4.7
pin 30 = 4.8

Resistors:
Here I'm not sure how to read the measurement because the value on the meter only flashes for a second, and every time I touch the pin I get a different reading. Should I be getting a steady reading like I do when I measure an uninstalled resister? I'm using the ground of the usb jack, but here's a list of the resistors I tested and weather they gave me a value or not.

atmega32
pins 6-8,31,14-21 all gave me readings in the 200 to 900 range
pin 11 sometimes gave me a neg reading, I didn't think there was polarity with the resistors, but again. I'm not even sure I'm doing it right, I'm using the ground pin 4 on the usb connector as a ground and just touching the pins you requested with the meter set to ohms and 2k. If I measure one of the resistors that was left over after making the board I get a Steady reading of the value of that resistor.
LCD
pin 1,2,3 all gave me readings
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Re: how can I know if my mac is truly communicating with the MD?

Postby dmitri » Sat Feb 07, 2009 4:18 pm

jeffbeckib wrote:voltage

LCD
pin 2 = 4.87
pin 3 = 2.8

Pic18f2550
pin 14 = 4.87
pin 20 = 3.35

atmega32
pin 9 = 4.7
pin 10 = 4.7
pin 30 = 4.8

Resistors:
Here I'm not sure how to read the measurement because the value on the meter only flashes for a second, and every time I touch the pin I get a different reading. Should I be getting a steady reading like I do when I measure an uninstalled resister? I'm using the ground of the usb jack, but here's a list of the resistors I tested and weather they gave me a value or not.

When it is done on a board, you measure resistance between given points, not the resistance of resistors.

atmega32
pins 6-8,31,14-21 all gave me readings in the 200 to 900 range
pin 11 sometimes gave me a neg reading, I didn't think there was polarity with the resistors, but again. I'm not even sure I'm doing it right, I'm using the ground pin 4 on the usb connector as a ground and just touching the pins you requested with the meter set to ohms and 2k. If I measure one of the resistors that was left over after making the board I get a Steady reading of the value of that resistor.
LCD
pin 1,2,3 all gave me readings

When you measure resistance between the ground on the USB and all other ground points you should get 0 (zero) Ohm resistance. For this reason when you measure resistance between the ground on the USB and the pins 11 and 31 of Atmega you should get 0 Ohm (or very close to it, like 1-2 Ohm) when measured in either direction (when you swap black and red probes).
Measure voltage on these pins as well when powered up. If you read anything but 0V on pins 11 and 31 you have a break between the ground on the USB and the pins 11 and 31 of Atmega. Of course, this suggestion is only true if you didn't mix up pin numbering again.
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Re: how can I know if my mac is truly communicating with the MD?

Postby jeffbeckib » Sat Feb 07, 2009 4:57 pm

ok pin 11 and 31 are measuring 0.00 on ohms and on voltage
pin 1 of LCD measures 0.00
pin 2 and 3 of LCD are giving random measurements. I'm still trying to understand why I don't get 1 static reading when checking these pins. I get a different reading every time I touch the same pin.
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Re: how can I know if my mac is truly communicating with the MD?

Postby dmitri » Sat Feb 07, 2009 5:05 pm

jeffbeckib wrote:ok pin 11 and 31 are measuring 0.00 on ohms and on voltage

So why it wasn't 0 in the previous measurement?

pin 1 of LCD measures 0.00
pin 2 and 3 of LCD are giving random measurements. I'm still trying to understand why I don't get 1 static reading when checking these pins. I get a different reading every time I touch the same pin.

Because of capacitors.
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