Cascadable 8x16 Rgb Led Matrix

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In this project I made cascadable 8x16 rgb led matrix and its controller.

Microchip's 18F2550 is used for its USB support.

RGB leds are driven by 74hc595 shift registers with resistors.

For animation and configuration data; 24C512 external eeprom is used.

Configuration and animation data is created by graphical user interface (gui) at computer and transferred to eeprom via USB

I made my rgb led matrix modules 8x16 pixel size. And they can be attached to make more large display area.

Step 1: Architecture

architecture

Animation and configuration data is created at computer by a gui.
then it is uploaded to control board via usb.
Micro controller unit (mcu) transfers this data to storage unit of board (eeprom).

When board is on action,
it first reads the configuration data:
time intervals between frames of animation , length of animation to show, working mode (solo or cascaded)

then it reads a chunk of animation data and send the data to shift registers to update the status of leds.

Common anode rgb leds are used.
leds are arranged 8 rows, 16 columns.
all anodes are connected to each other in a row. Shift registers controls one row at a time.
By multiplexing; 8 rows are updated very fast so continuous image is display.

for 8 rows -----------> one 8bit shift register is used for multiplexing.
for 16 rgb leds columns 16*3=48 --------> six 8bit shift register is used.

At solo mode one module is work as described above.

At cascade mode:
One board is become master board and send synchronization signal to other boards via serial peripheral interface (spi).
all boards display animations stored at their memory. And timing is arranged according to synchronization signal coming from master board.

Step 2: Hardware

Control board and rgb led matrix board can be separated.

Control board:
Microchip 18F2550
24c512 eeprom
74hc595 8bit shift register
B type usb connector
female male connectors
470 ohm resistor for green and blue led cathodes
560 ohm resistor for red led cathodes
switches, buttons, caps

RGB led matrix board:
8x16=128 common anode rgb led

Boards can be energized from USB port of PC or
via power adapter like 'USB power charger adapter' it can be energized from wall power plug

Step 3: Software

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    11 Discussions

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    ozguGeodeX

    Reply 9 months ago

    I uploaded sources.

    regards

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    thuuerta

    5 years ago on Step 2

    Could you show me the schematic please? Im a little lost with the Datasheet of the 18F2550. Thanks! :D

    1 reply
    0
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    ozguthuuerta

    Reply 9 months ago

    I uploaded sources.

    regards

    0
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    eungurean

    4 years ago on Introduction

    Well, this is probably the worst 'ible I've ever seen:

    - no schematic

    - no source code (not even compiled hex!)

    All you've done is a functional description (alias bragging).

    Useless.

    0
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    jmorales5

    4 years ago

    BUEN TRABAJO AMIGO,PERO TE FALTA PUBLICAR EL LINK PARA EL FIRMWARE DEL PIC Y EL SOFTWARE PARA EL PC.buscame en youtube como jose leonardo morales ledmatrix 18f25k20 ;)

    http://www.youtube.com/watch?v=t8sSk6adpBA

    0
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    GeodeX

    5 years ago on Step 2

    What is the value of the 4 capacitors used and what is the component right of the 20MHZ crystal on the pcb? I'm new to electronics and would appreciate you help.

    2 replies
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    ozguGeodeX

    Reply 5 years ago on Step 2

    in power lines 0.1mF (black ones)
    15pF at clock (little brown ones)
    right ot the crystal is a capacitor for USB line, its value is 220nF

    0
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    ozgu

    Reply 5 years ago on Introduction

    Thanks Beta Mode :)
    thanks for your precious suggestions.
    for the moment i'm working on MSGEQ7 for making vumeter:
    http://ozgunursal.blogspot.com/2013/04/7-kanall-vumetre-pixel-ledlerle.html
    i embed it on pixel leds. but can be implement to this work too.
    it needs some update for this post, i guess :)

    0
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    vitya

    6 years ago on Introduction

    Good job!
    Would you care to share the PIC's firmware (source files) too?