Using the SSD1306 based 128×64 OLED display

In the program showtime.lua (http://sourceforge.net/projects/nodemcu/files/showtime.lua) I use the OLED display mentioned above to display the time requested from (Google) server  .

In the initialization phase you have to decide which font should be used to display the text information.

-- graphic components
function prepare()
disp:setFont(u8g.font_6x10)
disp:setScale2x2()
disp:setFontRefHeightExtendedText()
disp:setDefaultForegroundColor()
disp:setFontPosTop()
end

The library U8glib (Universal Graphics Library for 8 Bit Embedded Systems) offers a lot of fonts.

Not all of them are available in the standard compilation of NodeMCU. A look to the file nodemcu-firmware/app/include/u8g_config.h shows us that the fonts 6×10 and chikita are available here.

// Configure U8glib fonts
// add a U8G_FONT_TABLE_ENTRY for each font you want to compile into the image

#define U8G_FONT_TABLE_ENTRY(font)
#define U8G_FONT_TABLE \
             U8G_FONT_TABLE_ENTRY(font_6x10) \
U8G_FONT_TABLE_ENTRY(font_chikita)
#undef U8G_FONT_TABLE_ENTRY

If you want to use other fonts you have to include them into this configuration file and recompile the whole project.

Using the SSD1306 based 128×64 OLED display

Last Phase

CoverThe analyst firm Gartner says that by 2020 there will be over 26 billion connected devices…that’s a lot of connections (some even estimate this number to be much higher, over 100 billion).

The IoT is a giant network of connected “things” (which also includes people).  The relationship will be between people-people, people-things, and things-things. The new rule for the future is going to be, “anything that can be connected, will be connected.”

In this book I will consider the frontend of the IoT – the so-called IoT node. This IoT node is connected to sensors and actors and to the network. Our IoT node here uses WLAN connectivity to the network by which it is very easy to integrate it in an existing office or home network.

This task can be fulfilled by a lot of wireless network capable microcontrollers as Arduino, Raspberry Pi, Beagle Bone and further more equipped with a Wifi device. But the use of such complex devices is not in focus here. Our goal is to use a very cheap device to build a compact IoT node.

The title of this book defines our goal – building an IoT Node for less than $ 15. A listing of expecting costs for the various components is given in the IoT Node Costs.

The ESP8266 microcontroller is the base for this journey.

The book is scheduled to appear in the autumn 2015. Here is the table of content. If you are interested in more details please leave a replay.

Last Phase