42 lines
1.5 KiB
Plaintext
42 lines
1.5 KiB
Plaintext
= Attaching a Max7219 driving an 8 digit 7 segment display via SPI
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This example code shows how to interface the Raspberry Pi Pico to a Max7219 driving an 8 digit 7 segment display. The particular device used is interfaced via SPI at 3.3v.
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The Max7219 datasheet can be found here https://datasheets.maximintegrated.com/en/ds/MAX7219-MAX7221.pdf
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== Wiring information
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Wiring up the device requires 5 jumpers as follows:
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* GPIO 17 (pin 22) Chip select -> CS on Max7219 board
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* GPIO 18 (pin 24) SCK/spi0_sclk -> CLK on Max7219 board
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* GPIO 19 (pin 25) MOSI/spi0_tx -> DIN on Max7219 board
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* 5v (pin 40) -> VCC on Max7219 board
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* GND (pin 38) -> GND on Max7219 board
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The example here uses SPI port 0. Power is supplied from the 5V pin.
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[NOTE]
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======
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There are many different manufacturers who sell boards with the Max7219. Whilst they all appear slightly different, they all have, at least, the same 5 pins required for power and communication. Please ensure you connect up as described in the previous paragraph.
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======
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== List of Files
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CMakeLists.txt:: CMake file to incorporate the example in to the examples build tree.
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max7219_8x7seg_spi.c:: The example code.
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== Bill of Materials
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.A list of materials required for the example
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[[max7219-bom-table]]
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[cols=3]
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|===
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| *Item* | *Quantity* | Details
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| Breadboard | 1 | generic part
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| Raspberry Pi Pico | 1 | https://www.raspberrypi.com/products/raspberry-pi-pico/
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| max7219 board with 8x7segment LEDs| 1 | generic part
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| M/M Jumper wires | 5 | generic part
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|===
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