diff --git a/README.md b/README.md
index c5c0d76..efa611b 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,36 @@
 # counter
 
+## Preparation
+
+
+Update:
+
+```
+apt update
+apt upgrade
+apt autoremove
+```
+
+
+Purge everything not required:
+
+```
+apt purge triggerhappy bluez wpasupplicant modemmanager avahi-daemon
+apt autoremove
+```
+
+Disable Bluetooth and WiFi at boot, put these lines in `/boot/firmware/config.txt`:
+
+```
+dtoverlay=disable-wifi
+dtoverlay=disable-bt
+```
+
+Install build chain and kernel headers:
+
+```
+apt install build-essential raspberrypi-kernel-headers git
+```
+
+
+
diff --git a/legacy/config.txt b/legacy/config.txt
new file mode 100755
index 0000000..8c5e3e2
--- /dev/null
+++ b/legacy/config.txt
@@ -0,0 +1,69 @@
+# For more options and information see
+# http://rpf.io/configtxt
+# Some settings may impact device functionality. See link above for details
+
+# uncomment if you get no picture on HDMI for a default "safe" mode
+#hdmi_safe=1
+
+# uncomment this if your display has a black border of unused pixels visible
+# and your display can output without overscan
+#disable_overscan=1
+
+# uncomment the following to adjust overscan. Use positive numbers if console
+# goes off screen, and negative if there is too much border
+#overscan_left=16
+#overscan_right=16
+#overscan_top=16
+#overscan_bottom=16
+
+# uncomment to force a console size. By default it will be display's size minus
+# overscan.
+#framebuffer_width=1280
+#framebuffer_height=720
+
+# uncomment if hdmi display is not detected and composite is being output
+#hdmi_force_hotplug=1
+
+# uncomment to force a specific HDMI mode (this will force VGA)
+#hdmi_group=1
+#hdmi_mode=1
+
+# uncomment to force a HDMI mode rather than DVI. This can make audio work in
+# DMT (computer monitor) modes
+#hdmi_drive=2
+
+# uncomment to increase signal to HDMI, if you have interference, blanking, or
+# no display
+#config_hdmi_boost=4
+
+# uncomment for composite PAL
+#sdtv_mode=2
+
+#uncomment to overclock the arm. 700 MHz is the default.
+#arm_freq=800
+
+# Uncomment some or all of these to enable the optional hardware interfaces
+#dtparam=i2c_arm=on
+#dtparam=i2s=on
+dtparam=spi=on
+
+# Uncomment this to enable infrared communication.
+#dtoverlay=gpio-ir,gpio_pin=17
+#dtoverlay=gpio-ir-tx,gpio_pin=18
+
+# Additional overlays and parameters are documented /boot/overlays/README
+
+# Enable audio (loads snd_bcm2835)
+dtparam=audio=on
+
+[pi4]
+# Enable DRM VC4 V3D driver on top of the dispmanx display stack
+dtoverlay=vc4-fkms-v3d
+max_framebuffers=2
+
+[all]
+#dtoverlay=vc4-fkms-v3d
+
+dtoverlay=pi3-disable-wifi
+dtoverlay=pi3-disable-bt
+
diff --git a/legacy/counter b/legacy/counter
new file mode 100755
index 0000000..cf94e4a
Binary files /dev/null and b/legacy/counter differ
diff --git a/legacy/counter.cfg b/legacy/counter.cfg
new file mode 100644
index 0000000..0d13827
--- /dev/null
+++ b/legacy/counter.cfg
@@ -0,0 +1,9 @@
+led = "on"
+
+sinkServer = "sink.hottis.de"
+sinkPort = 20169
+
+deviceId = "MainsCnt03"
+// sharedSecret has to have exactly 31 octets
+sharedSecret = "Wmxp**QwHxz#!6RaSSZK#AU7mdie#v*"
+
diff --git a/legacy/counter.service b/legacy/counter.service
new file mode 100644
index 0000000..3c3456f
--- /dev/null
+++ b/legacy/counter.service
@@ -0,0 +1,17 @@
+[Unit]
+Description=MainsFreqCounter
+Wants=network-online.target
+After=network-online.target
+
+
+[Service]
+Type=simple
+ExecStart=/opt/sbin/counter
+Restart=on-failure
+WorkingDirectory=/tmp
+
+[Install]
+Alias=Counter
+WantedBy=multi-user.target
+
+