Handy DCC Packet List

GLOBAL PACKETS

    00000000    RESET
    00000000
    00000000
------------------------------------------------------------------------------
    11111111    IDLE
    00000000
    11111111

MULTI-FUNCTION DECODER PACKETS

  [address] for decoders with 7 BIT ADDRESSES (Primary Addr. = 1 to 127):   
    0AAAAAAA                                                                
  [address] for decoders with 14 BIT ADDRESSES (Primary Addr. = 192 to 231):
    11AAAAAA                                                                
    AAAAAAAA                                                                

    [address]   14/28 STEP SPEED/DIRECTION PACKET
    01DsSSSS    s = LSB (28 step), or undefined (14 step)
    EEEEEEEE
------------------------------------------------------------------------------
    [address]   DIRECT (128 step) SPEED CONTROL
    00111111
    DSSSSSSS
    EEEEEEEE
------------------------------------------------------------------------------
    [address]   MULTI-FUNCTION GROUP 1 (5 on/off functions)
    100ddddd    
    EEEEEEEE
------------------------------------------------------------------------------
    [address]   MULTI-FUNCTION GROUP 2a (4 on/off functions)
    1011dddd    
    EEEEEEEE
------------------------------------------------------------------------------
    [address]   MULTI-FUNCTION GROUP 2b (2 variable functions)
    1010xxyy    xx and yy = 00 (reset), 01 (increment), 10 (decrement)
    EEEEEEEE

ACCESSORY DECODER PACKETS
for decoders with 10 BIT ADDRESSES (Primary Addr. = 128 to 191)

    10AAAAAA    TYPE 1 ACCESSORY (8 on/off functions)
    AAAAdaaa    aaa = 3 bit sub-address    d = on/off
    EEEEEEEE
------------------------------------------------------------------------------
    10AAAAAA    TYPE 2 ACCESSORY (2 variable functions)
    AAAAxxyy    xx and yy = 00 (reset), 01 (increment), 10 (decrement)
    EEEEEEEE

SERVICE MODE PACKETS
(preceded by RESET packet plus long preamble)

    01111RRR    Write 8-bit register using paged (3-bit) addressing
    DDDDDDDD
    EEEEEEEE
------------------------------------------------------------------------------
    01110RRR    Query 8-bit register using paged (3-bit) addressing
    DDDDDDDD
    EEEEEEEE
------------------------------------------------------------------------------
    011111AA    Write 8-bit register using direct (10-bit) addressing
    AAAAAAAA
    DDDDDDDD
    EEEEEEEE
------------------------------------------------------------------------------
    011101AA    Query 8-bit register using direct (10-bit) addressing
    AAAAAAAA
    DDDDDDDD
    EEEEEEEE
------------------------------------------------------------------------------
    011110AA    Write one bit in a register using direct (10-bit) addressing
    AAAAAAAA
    100D0BBB    D = bit value     BBB = bit position
    EEEEEEEE
------------------------------------------------------------------------------
    011100AA    Query one bit in a register using direct (10-bit) addressing
    AAAAAAAA
    100D0BBB    D=bit value  BBB=bit position
    EEEEEEEE

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