Vusb Mame Panel is not working - Unknown Device error

General discussions about V-USB, our firmware-only implementation of a low speed USB device on Atmel's AVR microcontrollers
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Vusb Mame Panel is not working - Unknown Device error

Post by easgard » Sat Feb 01, 2014 4:27 pm

I tried to do my own arcade machine console. I found v-usb mame panel ( I made and uploaded the hex code.

When I connect it to pc form usb, computer find it as “Unknown Device”.
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I’m not good at electronics. All I wanted to do is to create my mame panel. To find my mistake and it’s solution, I want to tell eveything I make.

When I found v-usb mame panel web page, I felt lucky. I downladed the circuit and sources. I bought this equipments with looking the bom list.

This is the BOM list

C4,C5==4u7===========CPOL-EUE2.5-6====E2,5-6 ======Resistor

This is what I bought

Part====Value==========Device===========What I Bought

C1,C2==22p===========C2.5/2===========22pF ceramic Capacitors
C3,C6==100n==========C5/C2.5===========100nF 63V Polyester Capacitors
C4,C5==4u7===========CPOL-EUE2.5-6====4.7uF 25 V Electrolytic Capacitor
D1=====1N4148DO35-7==1N4148DO35-7====1 N 4148
IC1====MEGA32-P======MEGA32-P=======ATMEGA32A PU**
IC2====LD117ADT33TR==LD117ADT33TR====LM 1117T - 3,3
Q1====12.000HZ======CRYSTALHC18U-V==12 MHz Crystal
R1====4k7============R-EU_0207/7=======4,7 Kohm 1/8 W Resistor
R2,R3==68============R-EU_0207/7=======68 ohm 1/8 W Resistor
R4=====1k5==========R-EU_0207/7========1,5 kohm 1/8 W Resistor
R5=====1M==========R-EU_0207/7========1 Mohm 1/4W Resistor

** I couldn’t find Atmega32. I bought Atmega32A. I found a document “Migrating from ATmega32 to ATmega32A” ( . I found ATmega 32 datasheet ( and ATmega32A datasheet ( ... asheet.pdf) But My experience is not enough to understand it

I watched pcb tutorials, made my pcb and upload it’s orginal hex file. I didn’t change any thing on source. I directly used it’s orginal hex file. When I connect it to pc form usb, computer find it as “Unknown Device”.

I found a troubleshooting document about "Device Not Recognized Errors" ( But My experience is not enough to understand it, again.

I need your help. What can be the problem?

1- Are the equipments that I used correct parts?
2- Is the problem about Atmega32A?
a- Do I have to change something on cicuit?
b- Do I have to change something in the source code?
3- Is the problem coming from another place?

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Re: Vusb Mame Panel is not working - Unknown Device error

Post by ulao » Mon Feb 03, 2014 7:43 pm

I dont know anything about Atmega32's but when you see that error its something in the USB side of the electronics. Most commonly the diodes. For example 1/4 watt diodes do not work in atmega158's and require 1/2 watt diodes. Also if the source code uses timers, these timer location may change from chip to chip. Check the data sheet for register location that may have moved. "Migrating from ATmega32 to ATmega32A" is going to tell you just that, so where is the disconnect? What is not clear? Without the source it may not be possible to switch chips.

Also remember Unknown Device, is not an error, its a general issue. So you have to hunt down the problem and fix it, no one can guess it for you.

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