#PiBlaster

Docs and source code for the PiBlaster project....

To be completed...

TODO: work in progress -- insert into dox

sudo aptitude install mpd mpc

sudo aptitude install python-pip

/etc/mpd.conf

audio_output { type "alsa" name "equal" device "plug:equal" }

sudo pip install python-mpd2

$ egrep -v '(^#|^\s*$|^\s*\t*#)' /etc/mpd.conf music_directory "/var/lib/mpd/music" playlist_directory "/var/lib/mpd/playlists" db_file "/var/lib/mpd/tag_cache" log_file "/var/log/mpd/mpd.log" pid_file "/var/run/mpd/pid" state_file "/var/lib/mpd/state" sticker_file "/var/lib/mpd/sticker.sql" user "root" bind_to_address "localhost" auto_update "yes" follow_outside_symlinks "yes" follow_inside_symlinks "yes" input { plugin "curl" } audio_output { type "alsa" name "My ALSA EQ" device "plug:plugequal" format "44100:16:2" # optional mixer_device "default" # optional mixer_control "PCM" # optional mixer_index "0" # optional }

filesystem_charset "UTF-8" id3v1_encoding "UTF-8"

mpc update

http://pythonhosted.org/python-mpd2/topics/getting-started.html

/etc/inittab

1:2345:respawn:/sbin/getty --autologin pi --noclear 38400 tty1

Download Qt >= 5.31 online installer and run it

$ chmod 755 qt-opensource-linux-x64-1.6.0-4-online.run
$ sudo qt-opensource-linux-x64-1.6.0-4-online.run

and install it to any location (/opt/Qt) is okay. Default selection of packages is ok, just make sure x86_64, armv7 are selected for Qt and QtCreator is selected for tools.

See qt docs on how connecting android devices. If configured correctly, just hit deploy button and wait for the application to start on your android device.

See installing images on linux

Download zip image for Raspbian (debian wheezy) and unzip it.

Insert empty SD card and make sure its not mounted Check the device name of the inserted SD card

$ dmesg | tail

it should print some information about the last connected device or so. You need the device name like [sdb] or [sdc]. Don't make a mistake here or you might mess up one of your working devices!

Copy image to SD card:

$ sudo dd bs=4M if=2014-06-20-wheezy-raspbian.img of=/dev/sdX

put the device later instead of the last X

Place SD card into PI and connect LAN, monitor and keyboard. In the software configuration select

• Expand Filesystem
• Advanced options -> ssh -> enable

and reboot. If connected via LAN you can now use ssh to connect to your PI. Default password for user pi is raspberry.

To set locale do

$ sudo dpkg-reconfigure locales

You can select en_US.UTF-8. Relogin to apply locales for your terminal.

To upgrade run

$ sudo aptitude update
$ sudo aptitude upgrade
$ sudo rpi-update

You can download and create the piblaster package right on your PI, all you need is cmake

$ sudo aptitude install cmake gdebi-core

You can skip this if you install a pre-packed package and install the dependencies by hand.

Now clone the git repo and create the package

$ cd /tmp
$ git clone https://github.com/ujac81/PiBlaster.git
$ cd PiBlaster/Pi/PyBlaster/
$ mkdir build
$ cd build
$ cmake ..
$ cpack

To install the package with dependencies run

$ sudo gdebi pyblaster-0.2.6-armhf.deb

Unblacklist i2c from /etc/modprobe.d/raspi-blacklist.conf (just comment out both lines) Follow instructions on Hifiberry site and make sure not to load the onboard sound module in /etc/modules. Also make sure to have made the Hifiberry made default in /etc/asound.conf.

If you want to install a software equalizer and enhance the sound quality by best speex encoding do:

$ sudo aptitude install libasound2-plugin-equal  libasound2-plugins

And add

defaults.pcm.rate_converter "speexrate_medium"

to /etc/asound.conf. You can also try "speexrate_best", which will consume more CPU, but not provide way better results. See alsa-dox.

For the equalizer add some lines to the /etc/asound.conf. Together with the Hifiberry device, mine looks like

pcm.!default  {
 type hw card 0
}
ctl.!default {
 type hw card 0
}
ctl.equal {
 type equal;
}
pcm.plugequal {
 type equal;
 slave.pcm "plughw:0,0";
}
pcm.equal {
 type plug;
 slave.pcm plugequal;
}

defaults.pcm.rate_converter "speexrate_medium"

To test your equalizer, use

$ alsamixer -D equal
$ mplayer -ao alsa:device=equal Foo.mp3.

Note: for later testing, make sure to run alsamixer -D equal as that user, who is playing the music. If e.g. mpd is run as root, you will have to do sudo alsamixer -D equal to get any effect of the equalizer.

To use i2c to control amps or other devices, install

$ sudo aptitude install i2c-tools

Unblacklist i2c from /etc/modprobe.d/raspi-blacklist.conf (just comment out both lines). Add

i2c-dev
i2c-bcm2708

to /etc/modules and reboot. Wire your I2C device to:

• 3.3V: Vi2c
• GPIO2: SDA (Raspberry PI B+ -- check for your device!!!)
• GPIO3: SCL (Raspberry PI B+ -- check for your device!!!)
• GROUND: GND Example for MAX9744 board using i2c

To control the amplifier mentioned above, use i2cset from command line:

$ sudo i2cset -y 1 0x4b 0x0 20

Where 1 is the i2c bus id, 0x4b is the device id of the amplifier (found via i2cdetect -y 1 or from documentation), 0x0 is the internal address for the volume setting and 20 is the volume value between 0 and 63 for this amp. Be careful, a setting of 35 or 40 might be very loud. Note: This applies for the MAX9744 class D amplifier board from adafruit. Your settings might differ.

Follow instructions on this page to wire and configure the remote control.

For a generic remote, use the lirc_rpi module with an extra option to tell which pin to use in GPIO mode (not board mode!). To load the module on boot, add these lines to /etc/modules file

lirc_dev
lirc_rpi gpio_in_pin=25

Tell lirc to use the default drivers. Settings in /etc/lirc/hardware.conf should be

LIRCD_ARGS=""
LOAD_MODULES=true
DRIVER="default"
DEVICE="/dev/lirc0"
MODULES="lirc_rpi"
LIRCD_CONF=""
LIRCMD_CONF=""

No teach the remote control. Google for irrecord or find a lircd.conf that matches your remote. To record use

$ sudo irrecord -d /dev/lirc0 /etc/lirc/lircd.conf

Store the file to /etc/lirc/lircd.conf. For my controller it looks like this:

# Please make this file available to others
# by sending it to <lirc@bartelmus.de>
#
# this config file was automatically generated
# using lirc-0.9.0-pre1(default) on Tue Oct  8 07:05:38 2013
#
# contributed by
#
# brand:                       /home/pi/lircd.conf
# model no. of remote control:
# devices being controlled by this remote:
#

begin remote

  name  /home/pi/lircd.conf
  bits           16
  flags SPACE_ENC|CONST_LENGTH
  eps            30
  aeps          100

  header       9006  4447
  one           594  1648
  zero          594   526
  ptrail        587
  repeat       9006  2210
  pre_data_bits   16
  pre_data       0xFD
  gap          107633
  toggle_bit_mask 0x0

      begin codes
          KEY_1                    0x08F7
          KEY_2                    0x8877
          KEY_3                    0x48B7
          KEY_4                    0x28D7
          KEY_5                    0xA857
          KEY_6                    0x6897
          KEY_7                    0x18E7
          KEY_8                    0x9867
          KEY_9                    0x58A7
          KEY_0                    0x30CF
          KEY_DOWN                 0xB04F
          KEY_LEFT                 0x10EF
          KEY_UP                   0xA05F
          KEY_RIGHT                0x50AF
          KEY_BACK                 0x708F
          KEY_ENTER                0x906F
          KEY_SETUP                0x20DF
          KEY_PAUSE                0x609F
          KEY_PAUSE                0x807F
          KEY_STOP                 0x609F
          KEY_VOLUMEUP             0x40BF
          KEY_VOLUMEDOWN           0x00FF
      end codes

end remote

The key naming is free, but there is an unwritten standard for the key naming. So maybe just use these names.

Now lirc daemon should be started on boot. To tell your application how to use the lirc commands, you need to configure the .lircrc file of the user running the application. As PiBlaster is run as root at the moment, place the file to /root/.lircrc

begin
  button = KEY_PAUSE
  prog = pyblaster
  config = playpause
end

begin
  button = KEY_UP
  prog = pyblaster
  config = playprev
end

begin
  button = KEY_DOWN
  prog = pyblaster
  config = playnext
end

begin
  button = KEY_VOLUMEUP
  prog = pyblaster
  config = volinc
  repeat = 2
end

begin
  button = KEY_VOLUMEDOWN
  prog = pyblaster
  config = voldec
  repeat = 2
end

The pyblaster software will check lircrc for commands for the program pyblaster and lirc will send the commands given after the config keyword to it. For the volume increase and decrease command we allow repeat (hold key works).

To run other commands via remote controller, you will have to start the irexec daemon, but its not required for pyblaster to work.

Per default PyBlaster will start on boot in terminal mode. This means it won't daemonize silently and just do its work, but will print to boot console. In terminal mode it will also prevent blanking of the screen. This is good for development/debugging, but might not be the right thing for you. To enable/disable terminal mode, check /etc/default/pyblaster file.

If using model B, set a static ethernet address in /etc/network/interfaces like

auto lo

iface lo inet loopback
iface eth0 inet static
        address 192.168.178.26
        gateway 192.168.178.1
        netmask 255.255.255.0
        dns-nameservers 192.168.178.1

allow-hotplug wlan0
iface wlan0 inet manual
        wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf

And set your nameserver in /etc/resolv.conf

nameserver 192.168.178.1

To overclock your Pi while add this to /boot/config.txt

arm_freq=1000
core_freq=500
sdram_freq=600
over_voltage=6
force_turbo=1

Note: Higher values will set a sticky bit inside the Pi and your warranty will be voided. This will boost your boot time by ~50%, but will lead to a higher power consumption. Also your Pi might run unstable. You have to play with the overclock settings to find something that suits your requirements. I disabled overclocking for my Pi because I want to save power and I found that my Pi runs unstable with these settings.