FalconFour posted up a ultra-optimized high-speed i2c library, check it out for better performance! Eagle CAD format schematic and board layout file (as well as a PNG of the schematic) are all available in the GitHub repository Fritzing object available in the Adafruit Fritzing Library You signed in with another tab or window. Reload to refresh your session. You signed out in another tab or window. Reload to refresh your session. Download the Adafruit LED Backpack library from github - This code provides support for the mini 8x8, 1.2" 8x8, 7-segment, bargraph, alphanumeric and bicolor LED matrix backpacks. To download click the ZIP download button, rename the uncompressed folder Adafruit_LEDBackpack. Check that the Adafruit_LEDBackpack folder contains Adafruit_LEDBackpack.cpp and Adafruit_LEDBackpack.h Place the Adafruit_LEDBackpack library folder your arduinosketchfolder/libraries/ folder. You may need to create the libraries subfolder if its your first library.

You'll also need to download the Adafruit GFX library - its not actually used for the 7-segment, its only for the matrix backpacks but its still required. Install just like the library above. Fritzing objects in Adafruit Fritzing library EagleCAD PCB files for all backpacks in GitHub The backpacks all use the HT16K33 chip solely for LED driving - the mini 8x8's use the 24 pin version and the others use the 28 pin vesion HT16K33 8x16 LED Backpack Breakout Schematic & fabrication print 8x8 0.8" LED Backpack 8x8 1.2" LED Backpack 8x8 1.2" Bi-Color LED Backpack 16x8 1.2" LED Backpacks Quad 0.54" 14-segment Alphanumeric Adafruit LED Matrix backpacks These are the Eagle CAD files for the Adafruit LED Backpack breakouts: Adafruit invests time and resources providing this open source design, please support Adafruit and open-source hardware by purchasing products from Adafruit! These displays use I2C to communicate, 2 pins are required to

There are multiple selectable I2C addresses. with 2 Address Select pins: 0x70, 0x71, 0x72 or 0x73. with 3 Address Select pins: 0x70 thru 0x77 All text above must be included in any redistribution Designed by Limor Fried/Ladyada for Adafruit Industries. Creative Commons Attribution/Share-Alike, all text above must be included in any redistributionecho backpack blower pb 500tWhat's better than a single LED? stihl backpack 430A fun way to make a small display is to use an 8x8 matrix or a 4-digit 7-segment display. kbs backpack simpleMatrices like these are 'multiplexed' - so to control 64 LEDs you need 16 pins. 55k backpackThat's a lot of pins, and there are driver chips like the MAX7219 that can control a matrix for you but there's a lot of wiring to set up and they take up a ton of space.

Here at Adafruit we feel your pain! After all, wouldn't it be awesome if you could control a matrix without tons of wiring? That's where these lovely LED matrix backpacks come in. We have them in three flavors - a mini 0.7" 8x8, a small 1.2" 8x8 and a 4-digit 0.56" 7-segment. They work perfectly with the matrices we stock in the Adafruit shop and make adding a bright little display trivial.The matrices use a driver chip that does all the heavy lifting for you: They have a built in clock so they multiplex the display. They use constant-current drivers for ultra-bright, consistent color (the images above are photographed at the dimmest setting to avoid overloading our camera!), 1/16 step display dimming, all via a simple I2C interface. These 1.2" matrix backpacks come with three address-selection jumpers so you can connect up to eight 1.2" 8x8's together (or a combination, such as four 1.2" 8x8's and four 7-segments, etc) on a single I2C bus.The product kit comes with:A bit of soldering is required to attach the matrix onto the backpack but its very easy to do and only takes about 5 minutes.

Of course, in classic Adafruit fashion, we also have a detailed tutorial showing you how to solder, wire and control the display. We even wrote a very nice library for the backpacks so you can get running in under half an hour, displaying images on the matrix or numbers on the 7-segment. If you've been eying matrix displays but hesitated because of the complexity, this is the solution you've been looking for!The itoa() stdlib C library function can be used to convert a number into a string, in a variety of bases (e.g. decimal, binary). The buffer must be large enough to hold the largest number, plus sign and terminating null: e.g. 32 bit base-10: "-2147483648\0" = 12 characters. The stdlib itoa() library routine adds around 600 bytes, the roll-your-own K&R implementation, which includes string.h, adds around 670 bytes. Using snprintf() from stdio.h adds just over 2200 bytes.A fun way to make a small linear display is to use two 12-bar Bi-color bar-graphs. However, this LED bargraph is 'multiplexed' - so to control all the 48 LEDs you need a lot of pins.

There are driver chips like the MAX7219 that can help control a bar-graph/matrix for you but there's a lot of wiring to set up and they take up a ton of space. After all, wouldn't it be awesome if you could control a colorful bargraph without tons of wiring? That's where this adorable LED bar-graph backpack comes in. Much like our 8x8 and 7-segment backpacks, this backpack pairs perfectly with our bar-graphs and manages all the LED control and multiplexing.The backpack uses a driver chip that does all the heavy lifting for you: It has a built in clock so it can multiplex the display. It uses constant-current drivers for ultra-bright, consistent color, 1/16 step display dimming, all via a simple I2C interface. The backpack comes with address-selection jumpers so you can connect up to eight of these bar-graphs on a single I2C bus. You can also mix-and-match the bar-graph breakout with our other types of I2C LED backpacks.The product kit comes with:A fully tested and assembled LED backpack stickTwo 12-bar bi-color bar-graphs4-pin headerA bit of soldering is required to attach the matrix onto the backpack but its very easy to do and only takes about 5 minutes.