Re: Can not access UDRC after updating software

Jeremy McDermond <mcdermj@...>

What is the output of “dpkg -l raspberrypi-kernel”?

I’m assuming that since you’re on kernel version 4.9 that you’re running wilderness. I recently made some changes to the repository in preparation for some future things. Wilderness is always considered to be unstable and subject to breakage at any point in time.

If your raspberrypi-kernel package version doesn’t have the word “compass” in it, you’ve gotten the stock Raspbian kernel. If that’s the case, you should bed able to do an “apt-get install udrc-dkms” to have the system compile and install drivers for you.

The udrc-support package does not include drivers for anything. It includes some configuration files for the ALSA UCM system that were intended to make it easier to get settings right for the various connectors on the UDRC.

Annaliese McDermond (NH6Z)

On May 28, 2018, at 6:55 PM, Herb Weiner <> wrote:


Thanks for your reply.

Would an apt-get update / upgrade have replaced the Compass kernel? Is there any way to tell? Is there any way to recover other than reinstalling Compass?

Note that the SeaPac 2017 tutorial on installing lighttpd explicitly suggested sudo apt-get update (RPi-workshop,session-1D,Tour-of-Applications) and never cautioned not to do sudo apt-get upgrade.

On a different note, what are the UDRC Support Files?


On May 28, 2018, at 6:06 PM, John D Hays - K7VE <> wrote:

The UDRC driver is a kernel driver. If your actions replaced the Compass kernel, then the driver is likely not available.

On Mon, May 28, 2018, 17:20 Herb Weiner <> wrote:

Thanks for your comment, which makes a lot of sense. So I tried:

pi@compass:~ $ apt search udrc
Sorting... Done
Full Text Search... Done
udrc-support/unstable,unstable 1.0 all
UDRC Support Files

pi@compass:~ $ sudo apt-get install udrc-support
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
0 upgraded, 1 newly installed, 0 to remove and 6 not upgraded.
Need to get 3,702 B of archives.
After this operation, 25.6 kB of additional disk space will be used.
Get:1 wilderness/main udrc-support all 1.0 [3,702 B]
Fetched 3,702 B in 0s (22.4 kB/s)
Selecting previously unselected package udrc-support.
(Reading database ... 143096 files and directories currently installed.)
Preparing to unpack .../udrc-support_1.0_all.deb ...
Unpacking udrc-support (1.0) ...
Setting up udrc-support (1.0) ...
pi@compass:~ $

So, I installed the UDRC Support Files (whatever they are), rebooted, and tried again. Unfortunately, this did not resolve the problem. But again, thanks for the suggestion.


On May 28, 2018, at 5:08 PM, Gayland Gump <> wrote:

Going out on a limb here but the update may have resulted in a kernel sans the udrc driver. I had similar problems when I used a build from the udrc wilderness or whatever the heck it is called.


On Mon, May 28, 2018 at 4:14 PM, Herb Weiner <> wrote:
After updating the software on my Raspberry Pi (apt-get update upgrade), I am no longer able to access my UDRC.

aplay -l shows

**** List of PLAYBACK Hardware Devices ****
card 0: ALSA [bcm2835 ALSA], device 0: bcm2835 ALSA [bcm2835 ALSA]
Subdevices: 8/8
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
Subdevice #2: subdevice #2
Subdevice #3: subdevice #3
Subdevice #4: subdevice #4
Subdevice #5: subdevice #5
Subdevice #6: subdevice #6
Subdevice #7: subdevice #7
card 0: ALSA [bcm2835 ALSA], device 1: bcm2835 ALSA [bcm2835 IEC958/HDMI]
Subdevices: 1/1
Subdevice #0: subdevice #0

I checked my /boot/config.txt and the last line (dtoverlay=udrc) was missing, so I added it back in and rebooted. The last two lines are now:


I then ran the following diagnostic commands that were recommended in a different thread, with the following results:

pi@compass:~ $ git clone
fatal: destination path 'n7nix' already exists and is not an empty directory.
pi@compass:~ $ cd n7nix/systemd/bin
pi@compass:~/n7nix/systemd/bin $ ./
Found a UDRC II
Name: hat
Product: Universal Digital Radio Controller II
Product ID: 0x0003
Product ver: 0x0001
UUID: f9697d40-293b-4bb6-9940-81b0decc3a53
Vendor: NW Digital Radio
pi@compass:~/n7nix/systemd/bin $ ./
Pi 3 Model B Mfg by Embest
Has WiFi
pi@compass:~/n7nix/systemd/bin $ ./
----- /proc/version
Linux version 4.9.80-v7+ (jenkins@jenkins) (gcc version 5.4.0 20160609 (Ubuntu/Linaro 5.4.0-6ubuntu1~16.04.9) ) #1 SMP Fri May 25 08:05:14 PDT 2018
----- /etc/*version
----- /etc/*release
PRETTY_NAME="Raspbian GNU/Linux 8 (jessie)"
NAME="Raspbian GNU/Linux"
VERSION="8 (jessie)"
----- lsb_release
No LSB modules are available.
Distributor ID: Raspbian
Description: Raspbian GNU/Linux 8.0 (jessie)
Release: 8.0
Codename: jessie
---- systemd
Static hostname: compass
Icon name: computer
Chassis: n/a
Machine ID: 493bfc529b1c440f94d670686c0263bc
Boot ID: 760f60dafb7349639167134b74bcbbc2
Operating System: Raspbian GNU/Linux 8 (jessie)
Kernel: Linux 4.9.80-v7+
Architecture: arm
----- direwolf
ver: Dire Wolf version 1.4
pi@compass:~/n7nix/systemd/bin $

./ does show that the UDRC is properly installed, so why can't aplay and related utilities find it?


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