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Subject: (no subject)
From: alankorr (alankorr_at_subdimension.com)
Date: 2002-01-13


Salut !

To Nicolas S.:

I can have a suggestion for you to speedup slightly your bit
streams : use 9-bit word instead of 8-bit, where the first
bit sent will act as a byte inverter.

For byte with total of bit 1 under or same total of bit 0
(pin state supposedly HI) :

  0x03 => L-H-L-H-L-H-L-HHH-LLL

For byte with total of bit 1 above total of bit 0 (pin state
supposedly HI) :

  0xFC => LLL-H-L-H-L-H-L-HHH-LLL instead of
L-HHH-LLL-HHH-LLL-HHH-LLL-H-L .

Finally the worst case will be 1.5 times longer than the
quickest byte to send instead of twice.

NOTE : if you send nible 0xF that way : LO - HIHIHI -
LOLOLOLOLOLOLO - HIHIHIHIHIHIHIHIHIHIHIHIHIHIHIHI, oh yes !
it will be very long !

Another suggestion, use a algorithm compression (LZSS could
be a simple and viable candidate) to compress your stream
before sending it to PC.

/alan

  

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