Adding a character display to your project or computer has never been easier with the new Adafruit USB or TTL serial backpack! This custom-designed PCB can connect to the back of any 16×2 or 20×4 character LCD and does everything you could want: printing text, automatic scrolling, setting the backlight, adjusting contrast, making custom characters, turning on and off the cursor, etc. It can even handle our RGB backlight LCDs with full 8-bit PWM control of the backlight. That means you can change the background color to anything you want – red, green, blue, pink, white, purple yellow, teal, salmon, chartreuse, or just leave it off for a neutral background. On non-RGB backlights you’ll be able to dim the backlight (it’s on the same pin as the ‘Red’ LED)
Inside this backpack is an USB-capable AT90USB162 chip that listens for commands both a mini-B USB port and a TTL serial input wire. The USB interface shows up as a COM/serial port on Windows/Mac/Linux. The backpack will automatically select data from whichever input is being used. For the USB connection, it will work at any baud rate. For the TTL connection, the default baud rate is 9600 but you can send it a command to set the baud rate to 2400, 4800, 9600, 19200, 28800, or 57600 baud. (The baud rate is flashed on the LCD during powerup). Any customizations such as baud rate, backlight color, brightness, splash screen, etc. are stored permanently EEPROM.
The command interface is compatible with the popular “Matrix Orbital” specifications so this backpack will work perfectly with computer applications or libraries that are expecting a “Matrix” LCD such as “LCD Smartie”. We added a few extra commands for the RGB backlight and setting the LCD size. If you don’t want to use the commands, you can just start sending ASCII to the LCD and it will magically appear as typed.
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.