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On PLAY Embedded you can find useful resources to getting started with embedded systems: media, examples and accurate descriptions are also provided. Come on, learn by doing!
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C Library design for embedded applications: tips and hints

C Library design: tips and hints

Write reusable code is one of the most powerful and time-saving thing that an embedded programmer should learn. Compose well-arranged libraries makes things easiest, especially when we want to add old code in a new project. Citing one of the most talented programmers I have ever met, “Well done code should be like a LEGO: must fit perfectly and without any effort”. So a good library should be quite abstract, with a simple hierarchy and should provide some well documented APIs.

Even if this is a generic embedded article, we will provide some concrete example.

When we want continue reading...

How to use an HD44780 based Liquid Crystal Display

How to use an HD44780 based Liquid Crystal Display

The HD44780 is a controller for display developed by Hitachi commonly used to manage alphanumeric dot matrix LCD. This controller is a standard de-facto for this kind of display. It is often used in industrial test equipment, networking equipment, vending machine and in embedded projects.

Compatible LCD screens are manufactured in several standard configurations. Common sizes are one row of eight characters (1×8), as well as 16×2, 20×2 and 20×4 formats. Larger custom sizes are made with 32, 40 and 80 characters and with 1, 2, 4 or 8 lines. The most commonly manufactured continue reading...

Using DHT11 with ChibiOS/RT

Using DHT11 with ChibiOS/RT

The DHT11 is a basic, low-cost digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air, and spits out a digital signal on the data pin (no analog input pins needed).

The communication on data pin occurs according to a non-standard protocol known as One-Wire protocol.

In this article we want to provide a demonstration for DHT11 compatible with ChibiOS/HAL 3.0, but also explain concepts inside that demo. Following that purpose we need for the DHT11 datasheet.

DHT11 Datasheet

Typical circuit requires a continue reading...

Registers and bit masks

Registers and bit masks

When I started with embedded my knowledge about programming was (and probably still is) very elementary. I often used logical operator like logical NOT (!), logical OR (| |) and logical AND (&&) but was almost ignoring the bitwise operators.SL Plugins

Handling registers is actually so simple that at first approach I wasted a couple of days and this was because bitwise operators are required to. Talking with friends of mine coming from Arduino, this problem seems to be much diffused. The trap seems to be a lack of basic knowledge of informatics and electronics. So in this continue reading...

ChibiCube hardware explained

ChibiCube hardware explained

By this article, we will show schematic of ChibiCube in order to understand how it works and hot it has been designed.

As mentioned in the previous article, ChibiCube addresses all its LEDs through the combination of anode and cathode signals. Each floor of the cube is configured as common anode, while the various cathode signals are separately connected to the outputs of the Shift Register. Setting the anode voltage to a value equal or greater than the high logical threshold of our SR, for the same principle illustrated in the tutorial Meeting SPI, we can address single continue reading...