Only three IO ports are used to drive the eight digit display. MAX7219 supports flicker free displays as well as cascading displays. You you can use it for Arduino. VCC and GND should not be connected reversed, so as not to burn the chip.
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This is the NEW Version Using the SMD MAX7219 . There is also an option for 5 dupont Female to Female approx 9.5cm Jumper Cables For more information on how to use the MAX7219 chip, see the datasheet.
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Only three IO ports are used to drive the eight digit display. MAX7219 supports flicker free displays as well as cascading displays. You you can use it for Arduino. Wiring instructions(for example, it can connect any IO port, modified the Port Definition in the program).
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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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The enclosure can be used with another boards as the ESP Mini module insert is removable.
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① LED is a unidirectional conductive device. Only current is allowed to flow from the positive pole to the negative pole. It turns on and emits light only when it is connected in the forward direction.
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1 X MAX7219CWG. ORIGINAL MAXIM DEVICE.
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