diff --git a/doc/mcu-examples/0BUILD b/doc/mcu-examples/0BUILD
index 986c8e1..7379902 100644
--- a/doc/mcu-examples/0BUILD
+++ b/doc/mcu-examples/0BUILD
@@ -4,6 +4,9 @@
 
   <subdirs>
     example_01
+    n28
+    n29
+    n30
   </subdirs>
 
 </gwbuild>
diff --git a/doc/mcu-examples/n28/0BUILD b/doc/mcu-examples/n28/0BUILD
new file mode 100644
index 0000000..0d51cc2
--- /dev/null
+++ b/doc/mcu-examples/n28/0BUILD
@@ -0,0 +1,13 @@
+<?xml?>
+
+<gwbuild>
+
+  <extradist>
+    README.md
+    n28_pcb_back.png
+    n28_pcb_front.png
+    n28_schematic.png
+  </extradist>
+
+</gwbuild>
+
diff --git a/doc/mcu-examples/n28/README.md b/doc/mcu-examples/n28/README.md
new file mode 100644
index 0000000..4f7ad29
--- /dev/null
+++ b/doc/mcu-examples/n28/README.md
@@ -0,0 +1,34 @@
+
+N28
+===
+
+
+N28 is a ATtiny84 based PCB with a door sensor and a temperature/humidity
+sensor.
+
+
+
+Overview
+--------
+
+- Role: Door sensor with temp sensor
+- MCU: AtTiny84
+- Connection: RJ45
+- COM: COM2W
+- Predecessor: N21, N16
+- Periphery:
+  - door sensor (TCRT1000)
+  - TWI interface
+    - SI7021 temperature and humidity sensor
+- Apps:
+  - NETWORK      : Basic network functionality (address setup etc.)
+  - REPORTSENSORS: report sensor data from temperature sensor etc.
+  - STATS        : periodically send stats data
+  - DOOR         : watch door/window sensor and notify about state changes
+
+- Values:
+  - SI7021_TEMP  : temperature
+  - SI7021_HUM   : humidity
+  - DOOR         : state of door/window (0=closed, >0=open)
+
+
diff --git a/doc/mcu-examples/n28/n28_pcb_back.png b/doc/mcu-examples/n28/n28_pcb_back.png
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diff --git a/doc/mcu-examples/n29/0BUILD b/doc/mcu-examples/n29/0BUILD
new file mode 100644
index 0000000..322d345
--- /dev/null
+++ b/doc/mcu-examples/n29/0BUILD
@@ -0,0 +1,13 @@
+<?xml?>
+
+<gwbuild>
+
+  <extradist>
+    README.md
+    n29_pcb_back.png
+    n29_pcb_front.png
+    n29_schematic.png
+  </extradist>
+
+</gwbuild>
+
diff --git a/doc/mcu-examples/n29/README.md b/doc/mcu-examples/n29/README.md
new file mode 100644
index 0000000..b90b1a3
--- /dev/null
+++ b/doc/mcu-examples/n29/README.md
@@ -0,0 +1,28 @@
+
+N29
+===
+
+
+N29 is a ATtiny84 based PCB with either a temperature/humidity sensor or
+a CO2 sensor. It also contains a motion detector and a Photo-LED/transistor
+for light measurement.
+
+
+
+Overview
+--------
+
+
+- Role: Air quality and climate sensors
+- MCU: AtTiny84
+- Connection: RJ45
+- COM: COM2W
+- Predecessor: N27, N24, N23, N19
+- Periphery:
+  - PIR sensor (AMN31112)
+  - TWI interface
+    - SI7021 temperature and humidity sensor
+      or
+    - SGP-30/40 air quality sensor
+  - Photo LED
+
diff --git a/doc/mcu-examples/n29/n29_pcb_back.png b/doc/mcu-examples/n29/n29_pcb_back.png
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index 0000000..bed1a9b
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diff --git a/doc/mcu-examples/n30/0BUILD b/doc/mcu-examples/n30/0BUILD
new file mode 100644
index 0000000..a965e3c
--- /dev/null
+++ b/doc/mcu-examples/n30/0BUILD
@@ -0,0 +1,13 @@
+<?xml?>
+
+<gwbuild>
+
+  <extradist>
+    README.md
+    n30_pcb_back.png
+    n30_pcb_front.png
+    n30_schematic.png
+  </extradist>
+
+</gwbuild>
+
diff --git a/doc/mcu-examples/n30/README.md b/doc/mcu-examples/n30/README.md
new file mode 100644
index 0000000..58dea04
--- /dev/null
+++ b/doc/mcu-examples/n30/README.md
@@ -0,0 +1,36 @@
+
+N30
+===
+
+N30 is a ATtiny84 based PCB with a temperature sensor and
+connections for LED stripes.
+
+Currently there is a driver for SK6812 RGBW stripes. The node
+supports event driven light control (e.g. turn on light when
+some other devices sends a motion detect message).
+
+The PCB is prepared to support SPI-controlled LED-Strips as well,
+but for now there is no software support for this (have to write
+a driver for it).
+
+
+Overview
+--------
+
+- Role: LED strip controller
+- MCU: AtTiny84
+- Frequency: 8MHz
+- Connection: RJ45
+- Predecessor: N22, N16
+- COM: COM2W
+- Periphery:
+  - LED strip connection (SK6812)
+  - OWI interface
+    - DS18B20 temperature sensor
+- Apps:
+  - NETWORK:       Basic network functionality (address setup etc.)
+  - REPORTSENSORS: report sensor data from temperature sensor etc.
+  - STATS        : periodically send stats data
+  - MA_LIGHT     : motion activated light
+
+
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