Objective Development Forums 2009-08-07T16:21:35+02:00 https://forums.obdev.at/app.php/feed/topic/3090 2009-08-07T16:21:35+02:00 2009-08-07T16:21:35+02:00 https://forums.obdev.at/viewtopic.php?t=3090&p=10413#p10413 <![CDATA[BootloadHID problem, "unable to enumerate USB device"]]>
I am trying to get BootloadHID working on my atmega324P, and it does not seem to work. A dmesg returns a long long list of this:

[ 7113.100044] hub 4-0:1.0: unable to enumerate USB device on port 2
[ 7114.028509] usb 4-2: new low speed USB device using uhci_hcd and address 37
[ 7114.092036] hub 4-0:1.0: unable to enumerate USB device on port 2
[ 7115.020013] usb 4-2: new low speed USB device using uhci_hcd and address 38
[ 7115.084763] hub 4-0:1.0: unable to enumerate USB device on port 2
[ 7116.016010] usb 4-2: new low speed USB device using uhci_hcd and address 39

I have looked through threads with similar problems so I will summarize my key things.

atmega324p on 5 volts, 16 MHz external crystal
1k8 pullup from D-
300 mW zener diodes BZX384 (C3V6) from ground to D+ and D-
#define USB_CFG_DMINUS_BIT 3 (PD3 INT1)
#define USB_CFG_DPLUS_BIT 2 (PD2 INT0)
68 Ohm between D and pins
Image
This is the circuit I copied.

I know for sure that the bootloader enters and stays in the "main event loop" because I have it turning on some LEDs

Do you have any suggestions on what the problem might be?

Thank you

Statistics: Posted by johan — Fri Aug 07, 2009 4:21 pm

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