max7219 4x 8x8 panels spi


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  1. #1
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    Default Re: max7219 4x 8x8 panels spi

    What is the logic in the packing of the characters into words?

    Ioannis

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    Default Re: max7219 4x 8x8 panels spi

    What is the logic in the packing of the characters into words?
    uses half the amount of flash memory when using 7bit numbers [pic16 flash is 14 bits wide] so you need to pack it.
    it takes very little time for the pic to unpack so there is no real penalty for a huge saving
    Warning I'm not a teacher

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    Default Re: max7219 4x 8x8 panels spi

    Yes, OK. But from 6 bytes you went to 3 words. Cannot understand the calculation you did.

    ;@ db 0x0E,0x10,0x1C,0x10,0x10,0x0E; // Code for char num 51 "3"
    @ dw 0x80e,0xe10,0x710

    0E=00001110, 10=00010000 and all these makes 80E?

    Ioannis

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    Default Re: max7219 4x 8x8 panels spi

    0xE=0b00001110, 0x10=0b00010000


    and all these makes 80E

    7 high bits | 7 low bits
    0x10<<7 | 0x0e &0x7f = 0x80e
    0b000100000000000 | 0b0001110 = 0b00010000001110 <==> 0x80e [14 bits]
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    Default Re: max7219 4x 8x8 panels spi

    After making the paper and pencil homework, I was amazed by your thinking! So simple, so clever, so efficient!

    Ioannis

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    Default Re: max7219 4x 8x8 panels spi

    Mikroe outputs the characters in columns but your data is in rows. Did you rotate them by hand or can GLCD do that?

    Ioannis

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    Default Re: max7219 4x 8x8 panels spi

    Last edited by richard; - 16th January 2022 at 11:54.
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