Tag Archives : arduino


Final observed and desired reliability curves

How I designed, built, and tested a temperature logger with Arduino (part 5)

The last post covered exciting results achieved with the temperature logger. It also covered a few problems, one of which caused the device to reset at random times. The random resets were occurring too often to make the device usable at sampling frequencies longer than 5 minutes, if at all. Particularly, as my failure analysis showed, the MTTF was […]


How I designed, built, and tested a temperature logger with Arduino (part 4)

In the last post I covered several lower-level refinements to the temperature logging device. Each refinement got us closer to the implementation. At each refinement, we also abstracted away details that were either out of scope of the model for our purposes (such as handling simultaneous interrupts) or simply not needed in subsequent refinements (such as what happens when […]

The final temperature logger schematic with LCD

How I designed, built, and tested a temperature logger with Arduino (part 3)

In the last post, I showed refinements to the original temperature logger system that further described different aspects and design choices. In order of appearance, each refinement: Described the rules and guards that fire when changing the recording frequency. Fixed a bug caused by an early design choice. Serialized part of the ASM to more closely resemble the serial imperative […]


How I designed, built, and tested a temperature logger with Arduino (part 2)

The Arduino-based temperature logger is shaping up. Based on the work thus far, what we have so far is: A ground model, which describes the requirements at an easy-to-understand level. Two refinements to the ground model that further describe the periodic and external-interrupt-driven operations of the device, together with more description on what it means to change the […]

Incremental refinement 4a

Practices in ASM methodology

How I designed, built, and tested a temperature logger with Arduino

The need for a temperature logger I tend to forget watering my plants regularly. When I remember to water them, almost invariably I notice they are wilted and almost dry. Poor things. To alleviate that problem, I’ve decided to automate this task. To that end, I’ve been working on a device that records temperatures using the Arduino UNO. My ultimate […]