We are excited to announce our newest product KontroLIR – the first Arduino compatible IR remote control. Users can now design their very own Infrared remote to work exactly how they want. The possibilities are unlimited. Customize the fully featured firmware within the Arduino IDE to your own needs or just add your own signals to the pre-configured 5 device/225+ buttons. Sketches are uploaded over Serial USB I/F from the Arduino IDE – just like any other sketch. KontroLIR features an ATmega328PB, a high power emitter, an indicator LED and is powered by 2xAAA alkaline batteries. Low power operation is already implemented with ~1uAmp idle current for long battery life. Available options include IR Receiver, IR Learner, 16 to 256KBytes I2c EEPROM and a serial USB adapter for uploading your sketch from the IDE. KontroLIR supports IRremote, IRLIB and is tightly integrated with our own AnalysIR Application.
In our previous post we showed how to generate stable IR carrier signals using the ESP8266 NodeMCU module. A feature of the original approach was that the output IR signal was inverted and required some additional circuitry to invert it again before transmission. Since the original post we have figured out a method to output a non-inverted or standard IR signal thus removing the need for the additional circuitry. This is achieved by using what turned out to be a very simple setting hidden deep in the ESP8266 UART registers which is covered below. Like all simple solutions it also threw up some other quirks of the ESP8266 NodeMCU, which were eventually overcome with the addition of a simple resistor. The Updated ESP8266 NodeMCU Backdoor uPWM Hack for IR signals is detailed below – including updated source firmware, new circuit diagram and explanation of the ‘quirk’. Read on….
We received our ESP8266 NodeMCU several months ago it has been difficult to find a working example of Hardware PWM to generate crisp Infrared carrier signals. Most posts we have read suggest that there is no PWM readily available on any of the supported platforms. As we have already shown with Arduinos and the Particle Photon we figured it would be possible to use a spare UART pin on the ESP8266 NodeMCU to achieve our goal. After some initial success we encountered some watchdog timeouts/resets and it seemed like the uPWM hack would not be possible on the ESP8266 Node MCU platform. For a few weeks we ‘parked’ the effort and today we decided to try again with all of the latest and updated firmware available from the ESP8266 community via the Arduino IDE. This time we were successful and the ESP8266 NodeMCU Backdoor uPWM Hack for IR signals using works!
A few months ago a new user to AnalysIR, from Canada, asked us to assist in adding ESP8266 NodeMCU Infrared decoding over WiFi into AnalysIR. We set about making some upgrades to AnalysIR for this and in double quick time he had AnalysIR accepting IR signals from the ESP8266 over WiFi. He stressed the ease of use of the support within the Arduino IDE for ESP8266 devices and he wasn’t kidding. This motivated us to go and order an ESP8266 for US$3.60 including shipping from Aliexpress. Just the other day the NodeMCU arrived, presumably delayed somewhat by the extended XMAS holidays & celebrations, in this part of the world. So we set about porting our existing firmware for Arduino & Photon over to the new device.
Marco is a volunteer for an organization (NSW Australia) that builds custom aids for people with disability, and has recently been looking at a project to create a ‘very large button’ IR remote control for a cable TV Set Top Box (STB). The custom unit needed basic functions (Channel Up/Down, Volume Up/Down and Power On/Off). Commercially available large button remotes have buttons that are still too small and/or they have too many buttons. Soon he hit a roadblock trying to capture some difficult Foxtel signals and searched all over the web looking for a solution. Needless to say, nothing worked out for him until he came across AnalysIR via Google. Once he started Troubleshooting the Big Button Infrared remote control with AnalysIR the root cause of his problems became obvious.
The final member of our first MakeIR series of devices & kits is the A.IR Shield Photon. This shield works out of the box with AnalysIR and is essentially plug & play, with additional prototyping options. The shield plugs into a (Particle) Photon with headers or pin-compatible clone. Although designed specifically for AnalysIR, users can also upload any sketches that run on the Photon for Infrared remote control projects by customising the included firmware. A.IR Shield Photon is built with only the highest quality IR components available and boasts dual Infrared emitters with configurable IR Power. The supplied firmware supports hardware PWM for sending IR signals.
We have provided a link below to the preliminary product data sheet and would welcome feedback on additional, nice to have or missing features, if any. Please read the data sheet for a more detailed description of the A.IR Photon shield.
Since we received our Photon several months ago it has been difficult to find a working example of Hardware PWM on the Photon. Initially, we ported our softPWM approach to the Photon, which is excellent. However, we figured it must be possible to use at least one of the spare UARTs on the Photon to achieve our goal. So first we started prototyping on the Arduino and quickly got a working example with some limitations – only 40 kHz and 33 kHz carrier frequencies were possible with the UART without delving into the registers a bit more. Then we moved the code over to the Photon, leveraging our previous softPWM examples, upgraded with the Arduino code – EUREKA! The Backdoor uPWM Hack on Photon for Infrared signals.
Dublin, Ireland – 17th April 2015. We are happy to announce the latest release of AnalysIR V1 preview #2 is now available for download by our backers & supporters. Existing users of AnalysIR will receive an email with instructions on how to download this version. New users will receive the details as part of the registration process.
A major highlight of this release is full AnalysIR support for our soon to be released LearnIR (IR Learner). LearnIR delivers the best performance available for receiving and sending Infrared signals with excellent accuracy.
A common question asked on forums is one about – Driving an Infrared Led directly from an Arduino pin. Although the answer may be obvious to anyone with at least a basic knowledge of Ohm’s Law, many are confused about how to choose a resistor value for optimum performance. Often, there is a debate about whether a resistor is required at all, given that the AVR pins are rated to deliver an absolute maximum of 40mA on a pin. (Note: All of the quoted specs in the data sheet are for test conditions of up to 20mA on a pin). Of course there are better ways to drive an IR LED with a transistor circuit or even a constant current circuit. However, in this post we consider only the direct drive circuit using a current limiting resistor, as illustrated in the diagram down below. Make sure to read the caveats at the end of this post.