Circular buffer provides an easy way to interact with events that take place on another thread or in an interrupt, it is not very efficient when used on a single thread because it uses atomic operations to ensure consistency of the buffer. It is an advanced collection for use by users that understand threading and writing interrupt safe code. There are two implementations, an optmized version for storing bytes, and a generic version that can be used to store any type, the generic version can also be created as a memory pool, where it works slightly differently.
TcMenu allows you to take over the display from the renderer very easily, once you own the display, you will be called back at regular intervals by the rendering class, and it is your responsibility to update the display at this time (if there are changes that require redrawing). You should never update the screen outside of these callbacks, as doing so would interfere with TcMenu rendering. There are two choices in this case, a functional approach based on providing a callback function, or an object oriented approach, where you provide an extension of CustomDrawing to the renderer.
MenuManager contains the functions to manage menu items, there is a global instance of this class called menuMgr. Here we present the most commonly used features, check out the reference docs for more details. There are a lot of iteration helper functions that can be used to navigate through menu structures. These are described further down the page. The following two reference documentation pages extend on the information here: Menu iteration reference docs MenuManager reference docs EEPROM support in menus Enabling next and back functionality To enable next, back or both, you provide the pin onto which you’ve connected the button for this function.
An I2C LCD backpack based on the PCF8574 chip provides an easy way to get started with LiquidCrystalIO on most Arduino boards. It is usually in one of two configurations as listed below. This library works correctly with the display and even has a shorthand way of creating the LCD for this case. Connectivity combinations for i2c backpacks Pin Option1 Option2 0 RS EN 1 RW RW 2 EN RS 3 Backlight Backlight 4 D4 D4 5 D5 D5 6 D6 D6 7 D7 D7 Construction for Option 1 outside of any functions (global):
There are often cases when you’ll need to run a micro controller from a battery power source. Unlike when running from mains power, every milli-amp matters. In these cases IoAbstraction’s task manager is able to integrate easily with most low power libraries. Task manager works by repeatedly calling the runLoop() function within loop() or main, during each loop task manager evaluates if any tasks are yet ready to run, and if they are it runs them.
TcMenu supports a wide range of rendering devices, from HD44780 based units using our LiquidCrystal fork through to mono OLEDs and full colour TFT displays using Adafruit_GFX and TFT_eSPI library. Over to the left you see an example of rendering to OLED device with title widgets. You can also easily take over the display to draw your own screen at any time. This is such a large subject, it deserves a page of its own.
Using a matrix keyboard with TcMenu is straightforward, we use the IoAbstraction Keyboard Manager component to handle the keyboard, along with a custom listener for tcMenu that feeds the menu manager with appropriate events upon key presses. This library allows you to connect your keyboard either using Arduino pins, or any supported IoAbstraction such as the I2C PCF8574 or MCP23017. Setting up the menu sketch for a Matrix Keyboard Before proceeding, it is recommended that you wire up your keyboard in accordance with the above linked keyboard manager page and any documentation that came with the keyboard.
TcMenu has considerable out of the box remote connectivity on both Arduino and mbed. With support for Ethernet2 library, UipEthernet library, ESP8266 WiFi, ESP32 WiFi and Serial (including Bluetooth Serial) to name a few connectors. Please pay close attention to the following classes in the reference documentation as they are mentioned frequently here: BaseRemoteServerConnection in reference docs TcMenuRemoteService in reference docs. Please bear in mind that TcMenu is able to support a wide range of remote connectors.
IoAbstraction has full support for interrupts on most devices, meaning we can connect a Rotary Encoder to an Arduino using a standard PCF8574 IO expander chip. In order to do this we need the PCF8574 /INT line to be connected to an Arduino pin that supports interrupts (such as pins 2 or 3). Further, you can also have switches handle push button input without polling, by initialising for interrupt, especially useful with IO exapnders.
Worked example: Building a timer For this example we will create a menu that has two top level menu items; a counter which counts down from the selected value, and a Boolean switch that turns on or off the countdown. It will also have a submenu with one menu item to control the notification method. So lets draw this out conceptually below menu root +- countdown, integer values 0 to 1000 seconds +- enabled, boolean YES, NO.