These are LED dot matrix displays with 32x8 BLUE 3mm LEDs. MAX7219 32x8 Dot Matrix BLUE LED Display. Daisy-chained MAX7219 driver chip for each 8x8 module. 1x MAX7219 32x8 Dot Matrix BLUE LED Display.
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1PCS MAX7219 Dot LED Matrix Module 8*8 MCU Control Module for Arduino 5V Interface Output Input Common Cathode
Aliexpress UK
The MAX7219 communicates with a MCU via a 3-wire SPI bus. Once the display is updated by the MCU, the MAX7219 then takes care of all the work of keeping the display refreshed, so it removes that overhead from the MCU which can be off doing other more important things.
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1pcs MAX7219 Dot Matrix Module Control Single Chip Microcomputer Module 4-in-1 Display 5P Line
Aliexpress UK
Encompasses a convenient 4-wire serial interface (4-pin SPI interface) to connect to all common microprocessors. Useful Links: (copy into a new browser window).
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MAX7219 Dot Matrix Module 32x8 4 in 1 LED Display Modules Drive with 5Pin Wires for Arduino Raspberry Pi
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MAXIM - MAX7219CNG.
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MAX7219 0.36 Inch 8 Bits Digital LED Display 7 Segment Module 5 Color Available for Arduino STM32 STC AVR
Aliexpress UK
The mini 8×8 Dot Matrix LED Display Module MAX7219 is based on the compact MAX7219 chip. MAX7219 8x8 Dot Matrix LED Display. 3.75mm Pixel Daisy-chainable MAX7219 driver chip. 1x MAX7219 8 x8 Dot Matrix LED Display.
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1pcs MAX7219 Dot Matrix Module 32x8 4 in 1 LED Display Modules Drive with 5Pin Wires for Arduino Raspberry Pi Red
Aliexpress UK
Single module can drive an 8 8 dot matrix common cathode. On the left block to an input port, an output port on the right. Modules with input and output interfaces, support for cascading multiple modules.
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MAX7219 Dot Matrix Module 32x8 4 in 1 LED Display Modules Drive with 5Pin Wires for Arduino Raspberry Pi
Aliexpress UK
A single module can drive a 8x8 dot matrix common cathode. The left side of the module to the input port, the right to an output port. Module with input and output interfaces, support for cascading multiple modules.
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Cascadable Digital Tube Display Module MAX7219 LED Display Supports Cascaded 8-bit Serial 3 IO Port Control
Aliexpress UK
A single module can drive a 8x8 dot matrix common cathode. The left side of the module to the input port, the right to an output port. Module with input and output interfaces, support for cascading multiple modules.
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MAX7219 8*8 Dot Matrix Module Red Light Microcontroller Module Display Module MCU LED Display Control Module
Aliexpress UK