When you're connecting your microcontrollers, you have some excellent networking options such as MQTT [1], Redis [2], and even SQL databases to choose from. If you work with low-end hardware or have some software limitations, memcached [3] is another good option to consider: It is a high-performance, distributed memory key-value caching solution. Memcached servers are supported on all major operating systems, and clients are available for almost all programming languages. Memcached is commonly used in back-end web applications, but it can also be used in distributed microcontroller projects.

Small systems only require network sockets to access a memcached server. This minimal requirement lets low-end hardware platforms such as gaming consoles (Figure 1) share information with Linux and Raspberry Pi systems. Bash users will be happy to hear that it only takes a one-liner to get or set a memcached key value.

This last winter was colder than usual, so I built a simple home temperature monitoring system using some low-end hardware (Figure 2). In this article, I'll show you how I used memcached with Bash, Python, and socket connections for my monitoring project.

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