Problem in digital part

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krinkel
 
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Problem in digital part

Post by krinkel »

Hi, after solving all problems in the analog part I have some problems in the digital part.
First of all, I can't change the tempo, it's stuck at about 70 bpm I also can't sync the xox to other gear or use my midi keyboard to use the midi play mode.
I also tested the midi thru and the midi thru works perfect.

A problem in the firmware maybe?

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antto
 
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Re: Problem in digital part

Post by antto »

yeah, that's the easiest thing you can try

krinkel
 
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Re: Problem in digital part

Post by krinkel »

Another problem is the oscilator doesn't get/generate the right voltage for the notes, I measured the voltages (between r90 and gnd like in the manual) and I got the following results

Low notes
C=5v
C#=5.08v
D=5.16v
D#=5.25v
E=5.33
F=4.08
F#=4.16
G=4.24
G#=4.33
A=4.41
A#=4.49
B=4.58
Middle notes
C=4.66
C#=4.75
D=4.83
D#=4.91
E=5v
F=5.08v
F#=5.16
G=5.25
G#=5.33
A=4.08
A#=4.16
B=4.24
High Notes
C=4.33
C#=4.41
D=4.49
D#=4.58
E=4.66
F=4.75
F#=4.83
G=4.91
G#=5
A=5.08
A#5.16
B=5.24

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mmm
 
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Re: Problem in digital part

Post by mmm »

As you can see the voltage "wraps around" at certain points within the octaves.

From the pattern it seems that both bit 4 and bit 5 are always on. Check pins 6 and 7 (this is in/out for bit 4) and 11 and 10 (this is in/out for bit 5) of IC 9.

bit 5 becomes active in the non-transposed octave from A upwards.
bit 4 is active for F in the lowest octave to G# non-transposed and then again from C# in the highest octave upwards.

krinkel
 
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Re: Problem in digital part

Post by krinkel »

What you said is correct, I measure 5.33v at pin 7 and 10 no matter which note is played, I also measure about 4.9v at pin 6 and 11

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mmm
 
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Re: Problem in digital part

Post by mmm »

krinkel wrote:What you said is correct, I measure 5.33v at pin 7 and 10 no matter which note is played, I also measure about 4.9v at pin 6 and 11
pin 6 and 11 come from the processor; that's why they are at roughly 5V; pin 7 and 10 are the outputs for IC9 and hence are at 5.33V.
Now we need to find out why pin 6 and 11 are always high. This problem can come either from the processor or perhaps from small copper bridges on the PCB.
Remove the processor, power up the xoxbox and measure again at pin 6 and 11 of IC 9.

krinkel
 
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Re: Problem in digital part

Post by krinkel »

Now I get 0v at pin 6 and 11 so I gues their is a problem with the cpu.
I tried to re upload the firmware but it failed, tomorow I will try it with another pc.

krinkel
 
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Re: Problem in digital part

Post by krinkel »

Can't find the right drivers for the xox on the other pc, any tips?

krinkel
 
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Re: Problem in digital part

Post by krinkel »

My computer now regognices the xox and the driver is installed but I still get the message xox not found...

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antto
 
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Re: Problem in digital part

Post by antto »

usb-serial drivers: http://www.ftdichip.com/Drivers/VCP.htm
if the drivers are installed and everything works properly - you should see a usb-serial device poping up into existance when you connect the x0xb0x (and it's switched on of course)
on windows you should check your device manager to find the serial device, and see which port name it has, could be something like "COM3" or some other number, then use THAT name in the control app
on linux, the device name will be "/dev/ttyUSB0" or such
on osx - something similar to linux

which control app are you using?
you can try with BANNED

krinkel
 
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Re: Problem in digital part

Post by krinkel »

Hi, I already found the link to the usb-serial driver in an old topic here.
After installing the driver my computer sees the x0xb0x at COM3 but after trying to connect it still says xoxbox not found...
(I tried both c0ntr0l and BANNED)
But I am buying a new cpu from someone who usses alternative cpu, I hope it will solve my problems

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antto
 
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Re: Problem in digital part

Post by antto »

alternative cpu?
i'm only aware of atmega162 (the original cpu) and the "x0xlarge" cpu (atmega2561)
in any case, the cpu must have a specific bootloader to work with the x0xb0x
the x0xlarge cpu has it, of course, but you can obtain atmega162 chips which have different (generic avr/arduino) bootloaders, which won't work here, and even with no bootloader at all
so whoever you're buying from, make sure that the chip is meant to be used with the x0xb0x and has a compatible bootloader

krinkel
 
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Re: Problem in digital part

Post by krinkel »

I am buying the atmega162 with the firmware of a used xoxbox, the guy I am buying from uses the n0nx0x firmware now (with atmega2561 chip).

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antto
 
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Re: Problem in digital part

Post by antto »

ah, okay

krinkel
 
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Re: Problem in digital part

Post by krinkel »

I replaced the cpu and everything is working perfectly, thanks I apreciate your help

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