From: Steinar H. Gunderson Date: Thu, 2 Mar 2006 12:49:39 +0000 (+0000) Subject: Update hamming.txt with information for our (31,26) code. X-Git-Url: https://git.sesse.net/?p=hamming;a=commitdiff_plain;h=3da82a2e70d9a9001cb011a944cb82fa925a6e35;ds=sidebyside Update hamming.txt with information for our (31,26) code. --- diff --git a/hamming.txt b/hamming.txt index aa9e947..1bd50d4 100644 --- a/hamming.txt +++ b/hamming.txt @@ -26,3 +26,31 @@ Strategy: lookup tables. Table of 2048 values -> 5 parity bits should be very cheap (consume 2kB of RAM for unsigned char, fits nicely into L1 cache and all). Do we want to encode extra information here? Probably not worth it at all... + +Expansion to (31,26): + + 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 +p1 p2 D1 p1 D2 D3 D4 p4 D5 D6 D7 D8 D9 DA DB p5 DC DD DE DF DG DH DI DJ DK DL DM DN DO DP DQ +-- xx xx xx xx xx xx xx xx xx xx xx xx xx xx xx + -- xx xx xx xx xx xx xx xx xx xx xx xx xx xx xx + -- xx xx xx xx xx xx xx xx xx xx xx xx xx xx xx + -- xx xx xx xx xx xx xx xx xx xx xx xx xx xx xx + -- xx xx xx xx xx xx xx xx xx xx xx xx xx xx xx + +Reordering: + + D1 D2 D3 D4 D5 D6 D7 D8 D9 DA DB DC DD DE DF DG DH DI DJ DK DL DM DN DO DP DQ +p1 xx xx xx xx xx xx xx xx xx xx xx xx xx xx xx +p2 xx xx xx xx xx xx xx xx xx xx xx xx xx xx xx +p3 xx xx xx xx xx xx xx xx xx xx xx xx xx xx xx +p4 xx xx xx xx xx xx xx xx xx xx xx xx xx xx xx +p5 xx xx xx xx xx xx xx xx xx xx xx xx xx xx xx + + +Converted to bitmasks: + +p1: 03 6a d5 55 +p2: 02 d9 b3 33 +p3: 01 c7 8f 0f +p4: 00 3f 80 ff +p5: 00 00 7f ff