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Hi,
Please check out what I found for encoding. There is one byte of data that does not make sense to me. If anyone knows what this is it's appreciated. Thanks!
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Sorry having problem uploading image...
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Here we go...
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Forgot to mention this is using Atmel 5577...
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the algorithm for this checksum is currently not known outside of farpointe. if you do make progress do share.
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a few samples were shown here as well: http://www.proxmark.org/forum/viewtopic.php?id=1655
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This has to be a CRC, I just don't know how CRCs really work at this point...how to generate them.
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I guess brute force could also work...there are only 7 bits and 128 possibilities. You could make a setup to try each possibility against a reader, and when the checksum is found...program a card with the result?! Not pretty but possible...
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I have 10 cards. Same FAC and with UIDs that follow each other.
If it can help, I will post them here.
Last edited by app_o1 (2015-01-09 11:53:35)
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It might help. More samples the better.
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.
Last edited by app_o1 (2015-01-09 12:11:57)
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One thing that I did find out is that all of the data in banks 0 to 4 have an effect on this checksum.
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Does the Proxmark have a command in it's command set to emulate a card?
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If you print all block data in bytes, it would be easier I'm too lazy to type in binary from a photo.
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How do you know the config block affects the checksum?
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Sorry my typo, all blocks 1-4 have an effect on the checksum. Block 0 has nothing to do with it.
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I have 10 cards. Same FAC and with UIDs that follow each other.
If it can help, I will post them here.
Change your mind?
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I have some sequential cards also...i can post the scans early next week...
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app_o1 wrote:I have 10 cards. Same FAC and with UIDs that follow each other.
If it can help, I will post them here.Change your mind?
Yes. It belongs to an office building and it is still being used today.
I can share in private. To whoever wants it (raw traces*10) please let me know your email address.
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Can you send it via ICQ, you have mine. If not I can put my email here.
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-
Last edited by app_o1 (2015-01-17 02:51:10)
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I have some sequential cards also...i can post the scans early next week...
can you post traces with printed card numbers?
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Sorry something came up this week but I can do the traces on Monday..
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Been working on a card emulator for brute force attack. Can't seem to find something appropriate
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Hmmm. Need a sim command that works first, then we could use lua to script the input attempts.
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OK so I promised you some card checksums. I set up a hacky mechanical setup using an air cylinder with an AT5577 tag attached to the end of its arm, a programmer, a reader and wrote some software. This Rube Goldberg contraption just started cycling through all of the checksums for site code zero, starting at tag ID 0. Here are some results for about 300 cards discovered for the first couple of hours of run time:
First number is Facility Code (decimal), Second number is Card ID (decimal) and third number is discovered checksum (hexadecimal). If you follow the Farpointe format guidelines outlined above and then replace the "UNKNOWN" byte with the HEX byte listed below for a particular card number the tag works on the reader everytime...now im either going to find an electronic way to discover these checksums or work on the actual algorithm that computes these checksums. In the mean time I am going to let the air cylinder chug away until I get to ID 65535 for all of FC 0. This is expected to take around 24 days. Who cares about the FC anyway? lol
(FC ID CS)
0 0 C7
0 1 1A
0 2 B9
0 3 64
0 4 E6
0 5 3B
0 6 98
0 7 45
0 8 58
0 9 85
0 10 26
0 11 FB
0 12 79
0 13 A4
0 14 07
0 15 DA
0 16 3D
0 17 E0
0 18 43
0 19 9E
0 20 1C
0 21 C1
0 22 62
0 23 BF
0 24 A2
0 25 7F
0 26 DC
0 27 01
0 28 83
0 29 5E
0 30 FD
0 31 20
0 32 F7
0 33 2A
0 34 89
0 35 54
0 36 D6
0 37 0B
0 38 A8
0 39 75
0 40 68
0 41 B5
0 42 16
0 43 CB
0 44 49
0 45 94
0 46 37
0 47 EA
0 48 0D
0 49 D0
0 50 73
0 51 AE
0 52 2C
0 53 F1
0 54 52
0 55 8F
0 56 92
0 57 4F
0 58 EC
0 59 31
0 60 B3
0 61 6E
0 62 CD
0 63 10
0 64 70
0 65 AD
0 66 0E
0 67 D3
0 68 51
0 69 8C
0 70 2F
0 71 F2
0 72 EF
0 73 32
0 75 4C
0 76 CE
0 77 13
0 78 B0
0 79 6D
0 80 8A
0 81 57
0 82 F4
0 83 29
0 84 AB
0 85 76
0 86 D5
0 87 08
0 88 15
0 89 C8
0 90 6B
0 91 B6
0 92 34
0 93 E9
0 94 4A
0 95 97
0 96 40
0 97 43
0 98 3E
0 99 E3
0 100 61
0 101 BC
0 102 1F
0 103 C2
0 104 DF
0 105 02
0 106 A1
0 107 7C
0 109 FE
0 110 80
0 111 5D
0 112 BA
0 113 67
0 114 C4
0 115 19
0 116 9B
0 117 46
0 118 E5
0 119 38
0 120 25
0 121 F8
0 122 5B
0 123 5D
0 124 04
0 125 D9
0 126 7A
0 127 A7
0 128 DA
0 130 A4
0 131 79
0 132 FB
0 133 26
0 134 85
0 135 86
0 136 45
0 137 98
0 138 3B
0 139 E6
0 140 64
0 141 B9
0 142 1A
0 143 C7
0 144 20
0 147 83
0 148 01
0 149 DC
0 150 7F
0 151 A2
0 152 BF
0 153 62
0 154 C1
0 155 1C
0 156 9E
0 157 43
0 158 E0
0 159 3D
0 160 3E
0 161 37
0 162 94
0 163 49
0 164 CB
0 165 16
0 166 B5
0 167 68
0 168 75
0 169 A8
0 170 0B
0 171 D6
0 172 54
0 173 89
0 174 2A
0 175 F7
0 176 F8
0 177 CD
0 178 6E
0 180 31
0 181 EC
0 182 4F
0 183 92
0 184 8F
0 185 52
0 186 F1
0 187 2C
0 188 AE
0 189 73
0 190 D0
0 191 0D
0 192 6D
0 193 B0
0 194 13
0 195 CE
0 196 4C
0 197 91
0 198 32
0 199 EF
0 200 F2
0 201 2F
0 202 8C
0 203 51
0 204 D3
0 205 0E
0 206 AD
0 207 70
0 208 97
0 209 4A
0 210 E9
0 211 34
0 212 B6
0 213 6B
0 214 C8
0 216 08
0 217 D5
0 218 76
0 219 AB
0 220 29
0 221 F4
0 222 57
0 223 8A
0 224 5D
0 225 80
0 226 23
0 228 FE
0 229 A1
0 230 02
0 231 DF
0 232 C2
0 233 1F
0 234 20
0 235 61
0 236 E3
0 237 3E
0 238 9D
0 239 40
0 240 A7
0 241 7A
0 242 D9
0 243 04
0 244 86
0 245 5B
0 246 F8
0 247 25
0 248 38
0 249 E5
0 250 46
0 251 9B
0 252 19
0 253 C4
0 254 67
0 255 BA
0 256 97
0 257 4A
0 258 E9
0 259 34
0 260 B6
0 261 6B
0 262 C8
0 263 15
0 264 08
0 265 D5
0 266 76
0 267 AB
0 268 29
0 269 F4
0 270 58
0 271 8A
0 272 6D
0 273 B0
0 274 13
0 275 CE
0 276 4C
0 277 91
0 278 32
0 279 EF
0 280 F2
0 282 8C
0 283 51
0 284 D5
0 285 0E
0 286 AD
0 287 70
0 288 A7
0 289 7A
0 291 04
0 292 86
0 293 5B
0 294 F8
0 295 25
0 296 38
0 297 E5
0 298 46
0 299 9B
0 300 19
0 301 C4
0 302 67
0 303 BA
0 304 5E
0 305 80
0 306 23
0 308 FE
0 309 A1
0 310 02
0 311 DF
0 312 C2
0 313 1F
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The contraption...
Last edited by hkplus (2015-11-26 08:09:46)
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Forgot to mention, that the "unknown" bytes provided include the proper odd parity bit. That poor 5577 eeprom is going to have a brain hemorrhage considering all of the continuous write cycles it's experiencing. Arm moves back and forth about every 500 mS.
Last edited by hkplus (2015-01-24 05:22:25)
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Sweet! I'll take a look at the samples soon. It would be great to do the same thing just incrementing the fc (nothing else).
And we could shorten the list of numbers significantly by just running 1 binary bit (or 2^x where x starts at 0 and increments). That would tell us how the checksum calc is affected by each bit.
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Is the arm to remove the tag from the reader field?
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I can run other site codes and IDs...whatever you want because I wrote the control software. Yes the arm is to move the card out of the field of the Farpointe reader and over the programmer. I started with a 4" long air cylinder, but it was not enough distance, the reader kept messing up the programmer, so I moved to an 6" air cylinder and put the thing in a steel surplus electrical box that seems to work as a shield. The programmer is an Atmel (GIS brand) programmer. I used the GIS .DLL and wrote a control program in VB.NET to control the programmer. The device that drives the valve is actually an access control. It has an open command set and you send commands to it via TCPIP. I am using it's relay, that is normally used to open doors, to drive the valve that runs the air cylinder under software control. I am also using it's 26 bit Wiegand port...if the access control sees anything come off of the reader, it converts the reader's Wiegand data to decimal and sends it back to my control software over the same TCPIP connection that is used to control the relay. Everytime the arm moves into the reader, I wait for up to 500 mS to see if data is coming off of the reader via the access control. If it sees data, that means that the correct checksum was found and I record the results in a .TXT file. If nothing comes back, then I increment the checksum and try the process again. It's hacky but it works and reliably. I had to add a verification to the write cycle on the card to retry the write if the program cycle fails, so I retry the write up to 5 times...this keeps the setup running unattended. I can start on Facility Code 1 on Monday or some other range of ID if you wish. I understand your request for incrementing one bit...I will get this for you also. I tried to make an electronic card emulator, but I could not get the thing to work right. I used an Atmel AVR processor hooked up to a coil that I pulled out of a clamshell card, but I could not get the firmware correct to work...yet. I will try to work on finding IDs 0-300 on FC 1 next week...I have a feeling that there is some type of XOR circuit/algorithm going on with the checksum.
Last edited by hkplus (2015-03-20 02:22:24)
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I'd be very interested in a complete list of 1 bit values with checksums. Example:
0000000000000000
0000000000000001
0000000000000010
0000000000000100
0000000000001000
0000000000010000
...
For both card number and fc, with checksums
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Let me work on that for you next week...:) It seems that you have a few of these now...card numbers 1,2,4,8,16 and others?
Last edited by hkplus (2015-01-24 06:06:58)
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Card numbers 1 and 2 are like what you are asking...one bit position change generates a huge change in the checksum...which is why I think it's an XOR train of some type...
0 1 1A
0 2 B9
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Yep, we have 0 through 256.
So we all we need for the card number is 512, 1024, 2048, 4096, 8192, 16384, 32786
Then 1,2,4,8,16,32,64,128 for the fc
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Except without the wp it is
0 1 1A
0 2 39
0 3 64
0 4 66
Right?
Last edited by marshmellow (2015-01-24 06:31:21)
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The other thing is with all those parities one bit change could change 2 or 3 other parity bits. If those parity bits are part of the calc it will make it a little more difficult.
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The other thing is with all those parities one bit change could change 2 or 3 other parity bits. If those parity bits are part of the calc it will make it a little more difficult.
The Wiegand parity is not in the "unknown" byte. ID 1 and ID 2 should have the same lower wiegand odd parity. My software calculates the odd parity over the first seven bits of the checksum byte then adds this parity to the LSB of the unknown byte. Did I answer your question? I am pretty sure that the parity bits in the Farpointe Manchester encoding do change the checksum value.
Last edited by hkplus (2015-01-24 06:44:27)
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Except without the wp it is
0 1 1A
0 2 39
0 3 64
0 4 66Right?
I am not sure where you are getting these numbers from?
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sorry i misunderstood your "includes parity" comment. i understand now.
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Just browsed a bit with my mobile... Hava you seen that if you start at 27:01. Follow the crcs upwards. Then look at 148:01, follow the crcs downwards. Its the same sequence. Haven:t got a computer right now, so I can't reallly explore it further atm. But may be a clue?
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More checksums...the contraption broke down for a bit when the actual prox tag physically broke off of the arm somehow...
0 0 C7
0 1 1A
0 2 B9
0 3 64
0 4 E6
0 5 3B
0 6 98
0 7 45
0 8 58
0 9 85
0 10 26
0 11 FB
0 12 79
0 13 A4
0 14 07
0 15 DA
0 16 3D
0 17 E0
0 18 43
0 19 9E
0 20 1C
0 21 C1
0 22 62
0 23 BF
0 24 A2
0 25 7F
0 26 DC
0 27 01
0 28 83
0 29 5E
0 30 FD
0 31 20
0 32 F7
0 33 2A
0 34 89
0 35 54
0 36 D6
0 37 0B
0 38 A8
0 39 75
0 40 68
0 41 B5
0 42 16
0 43 CB
0 44 49
0 45 94
0 46 37
0 47 EA
0 48 0D
0 49 D0
0 50 73
0 51 AE
0 52 2C
0 53 F1
0 54 52
0 55 8F
0 56 92
0 57 4F
0 58 EC
0 59 31
0 60 B3
0 61 6E
0 62 CD
0 63 10
0 64 70
0 65 AD
0 66 0E
0 67 D3
0 68 51
0 69 8C
0 70 2F
0 71 F2
0 72 EF
0 73 32
0 75 4C
0 76 CE
0 77 13
0 78 B0
0 79 6D
0 80 8A
0 81 57
0 82 F4
0 83 29
0 84 AB
0 85 76
0 86 D5
0 87 08
0 88 15
0 89 C8
0 90 6B
0 91 B6
0 92 34
0 93 E9
0 94 4A
0 95 97
0 96 40
0 97 43
0 98 3E
0 99 E3
0 100 61
0 101 BC
0 102 1F
0 103 C2
0 104 DF
0 105 02
0 106 A1
0 107 7C
0 109 FE
0 110 80
0 111 5D
0 112 BA
0 113 67
0 114 C4
0 115 19
0 116 9B
0 117 46
0 118 E5
0 119 38
0 120 25
0 121 F8
0 122 5B
0 123 5D
0 124 04
0 125 D9
0 126 7A
0 127 A7
0 128 DA
0 130 A4
0 131 79
0 132 FB
0 133 26
0 134 85
0 135 86
0 136 45
0 137 98
0 138 3B
0 139 E6
0 140 64
0 141 B9
0 142 1A
0 143 C7
0 144 20
0 147 83
0 148 01
0 149 DC
0 150 7F
0 151 A2
0 152 BF
0 153 62
0 154 C1
0 155 1C
0 156 9E
0 157 43
0 158 E0
0 159 3D
0 160 3E
0 161 37
0 162 94
0 163 49
0 164 CB
0 165 16
0 166 B5
0 167 68
0 168 75
0 169 A8
0 170 0B
0 171 D6
0 172 54
0 173 89
0 174 2A
0 175 F7
0 176 F8
0 177 CD
0 178 6E
0 180 31
0 181 EC
0 182 4F
0 183 92
0 184 8F
0 185 52
0 186 F1
0 187 2C
0 188 AE
0 189 73
0 190 D0
0 191 0D
0 192 6D
0 193 B0
0 194 13
0 195 CE
0 196 4C
0 197 91
0 198 32
0 199 EF
0 200 F2
0 201 2F
0 202 8C
0 203 51
0 204 D3
0 205 0E
0 206 AD
0 207 70
0 208 97
0 209 4A
0 210 E9
0 211 34
0 212 B6
0 213 6B
0 214 C8
0 216 08
0 217 D5
0 218 76
0 219 AB
0 220 29
0 221 F4
0 222 57
0 223 8A
0 224 5D
0 225 80
0 226 23
0 228 FE
0 229 A1
0 230 02
0 231 DF
0 232 C2
0 233 1F
0 234 20
0 235 61
0 236 E3
0 237 3E
0 238 9D
0 239 40
0 240 A7
0 241 7A
0 242 D9
0 243 04
0 244 86
0 245 5B
0 246 F8
0 247 25
0 248 38
0 249 E5
0 250 46
0 251 9B
0 252 19
0 253 C4
0 254 67
0 255 BA
0 256 97
0 257 4A
0 258 E9
0 259 34
0 260 B6
0 261 6B
0 262 C8
0 263 15
0 264 08
0 265 D5
0 266 76
0 267 AB
0 268 29
0 269 F4
0 270 58
0 271 8A
0 272 6D
0 273 B0
0 274 13
0 275 CE
0 276 4C
0 277 91
0 278 32
0 279 EF
0 280 F2
0 282 8C
0 283 51
0 284 D5
0 285 0E
0 286 AD
0 287 70
0 288 A7
0 289 7A
0 291 04
0 292 86
0 293 5B
0 294 F8
0 295 25
0 296 38
0 297 E5
0 298 46
0 299 9B
0 300 19
0 301 C4
0 302 67
0 303 BA
0 304 5E
0 305 80
0 306 23
0 308 FE
0 309 A1
0 310 02
0 311 DF
0 312 C2
0 313 1F
0 314 BC
0 315 61
0 316 E3
0 317 3E
0 318 9D
0 319 9E
0 320 20
0 321 FD
0 322 5E
0 323 83
0 324 01
0 325 DC
0 326 7F
0 327 A2
0 328 BF
0 329 62
0 330 C1
0 331 1C
0 332 9E
0 333 43
0 334 E0
0 335 3D
0 336 DA
0 337 07
0 338 A4
0 339 79
0 340 FB
0 341 26
0 343 58
0 344 45
0 345 98
0 346 3D
0 347 E6
0 348 64
0 349 B9
0 350 1A
0 351 C7
0 352 10
0 353 CD
0 354 6E
0 355 B3
0 356 31
0 357 EC
0 358 4F
0 359 92
0 360 8F
0 362 F1
0 363 2C
0 364 2F
0 365 73
0 366 D0
0 367 0D
0 368 EA
0 369 37
0 370 94
0 371 49
0 372 CB
0 373 16
0 374 B5
0 375 68
0 376 75
0 377 A8
0 378 0B
0 379 D6
0 380 54
0 381 89
0 382 2A
0 383 F7
0 384 8A
0 385 57
0 386 F4
0 387 29
0 388 AB
0 389 76
0 390 D5
0 391 08
0 392 15
0 393 C8
0 394 6B
0 395 B6
0 396 34
0 397 E9
0 398 4A
0 399 97
0 400 70
0 401 AD
0 402 0E
0 403 D3
0 404 51
0 405 8C
0 406 2F
0 407 F2
0 408 EF
0 409 32
0 410 91
0 411 4C
0 412 CE
0 413 13
0 414 B0
0 415 B3
0 416 BA
0 417 67
0 418 C4
0 419 19
0 420 9B
0 421 46
0 422 E5
0 423 38
0 424 25
0 425 F8
0 426 5B
0 427 86
0 428 89
0 429 D9
0 430 7A
0 431 A7
0 432 40
0 433 9D
0 434 3E
0 435 E3
0 436 61
0 437 BC
0 438 1F
0 439 C2
0 440 DF
0 441 02
0 442 A1
0 443 7C
0 444 7F
0 445 23
0 447 5D
0 448 3D
0 449 E0
0 450 43
0 451 9E
0 452 1C
0 453 C1
0 454 62
0 455 BF
0 456 C1
0 457 7F
0 458 DC
0 459 01
0 460 02
0 461 5E
0 462 FD
0 463 20
0 464 C7
0 465 1A
0 466 B9
0 467 64
0 468 E6
0 469 3B
0 470 98
0 471 45
0 472 58
0 473 85
0 474 26
0 475 FB
0 476 79
0 477 A4
0 478 07
0 479 DA
0 480 0D
0 481 D0
0 482 73
0 483 AE
0 484 2C
0 485 F1
0 486 52
0 487 54
0 488 92
0 489 94
0 490 EC
0 491 31
0 492 B3
0 493 6E
0 494 CD
0 495 10
0 496 F7
0 497 2A
0 499 54
0 500 57
0 501 0B
0 502 A8
0 503 75
0 504 68
0 505 B5
0 506 B6
0 507 CB
0 508 49
0 509 94
0 511 EA
0 512 0D
0 513 D0
0 514 73
0 515 AE
0 516 2C
0 517 F1
0 518 52
0 519 8F
0 521 4F
0 522 EC
0 523 31
0 524 B3
0 525 6E
0 526 CD
0 527 10
0 528 F7
0 529 2A
0 530 89
0 531 54
0 532 D6
0 533 0B
0 534 A8
0 535 75
0 536 68
0 537 B5
0 538 16
0 539 CB
0 540 49
0 541 94
0 542 37
0 543 EA
0 544 3D
0 545 E0
0 546 43
0 547 9E
0 548 1C
0 549 C1
0 550 62
0 551 BF
0 552 A2
0 553 7F
0 554 DC
0 555 01
0 556 83
0 557 5E
0 558 FD
0 559 20
0 560 C8
0 561 1A
0 562 B9
0 563 64
0 564 E6
0 565 3B
0 566 98
0 567 45
0 568 58
0 569 85
0 570 26
0 571 FB
0 572 79
0 573 A4
0 574 07
0 575 DA
0 576 BA
0 577 67
0 578 C4
0 579 19
0 580 9B
0 581 46
0 582 E5
0 583 38
0 584 25
0 585 F8
0 586 5B
0 587 86
0 588 04
0 589 D9
0 590 7A
0 591 A7
0 592 40
0 593 9D
0 594 3E
0 595 E3
0 596 61
0 597 BC
0 598 1F
0 599 C2
0 600 DF
0 601 02
0 602 A1
0 603 7C
0 605 FE
0 606 80
0 607 5D
0 608 8A
0 609 57
0 611 29
0 612 AB
0 613 76
0 614 D5
0 615 08
0 616 15
0 617 C8
0 618 6B
0 619 B6
0 620 34
0 621 EA
0 622 4A
0 623 97
0 624 70
0 625 AD
0 626 0E
0 627 D3
0 628 51
0 629 8C
0 630 2F
0 631 F2
0 632 EF
0 633 32
0 634 91
0 635 4C
0 636 CE
0 637 13
0 638 B0
0 639 6D
0 640 10
0 641 CD
0 642 6E
0 643 B3
0 644 31
0 645 EC
0 646 4F
0 647 92
0 648 8F
0 649 52
0 650 F1
0 651 2C
0 652 AE
0 653 75
0 654 D0
0 655 0D
0 656 EA
0 657 37
0 658 94
0 659 49
0 660 CB
0 661 16
0 662 B5
0 663 68
0 664 75
0 665 A8
0 666 0B
0 667 D6
0 668 54
0 669 89
0 670 2A
0 671 F8
0 672 20
0 673 FD
0 674 5E
0 675 83
0 676 01
0 677 DC
0 678 7F
0 679 A2
0 680 BF
0 681 62
0 682 C1
0 683 1C
0 684 9E
0 685 43
0 686 E0
0 687 3D
0 688 DA
0 689 07
0 690 A4
0 691 79
0 692 FB
0 693 26
0 694 85
0 695 58
0 696 45
0 697 98
0 698 3B
0 699 E9
0 700 64
0 701 B9
0 702 1A
0 703 C7
0 704 A7
0 705 7A
0 706 D9
0 707 04
0 708 86
0 709 5B
0 710 F8
0 711 25
0 712 38
0 713 E5
0 714 46
0 715 9B
0 716 19
0 717 C4
0 718 67
0 719 BA
0 720 5D
0 721 80
0 722 23
0 724 FE
0 725 A1
0 726 02
0 727 DF
0 728 C2
0 729 1F
0 730 BC
0 731 61
0 732 E3
0 733 3E
0 734 9D
0 735 40
0 736 97
0 737 4A
0 738 E9
0 739 34
0 740 B6
0 741 6B
0 742 C8
0 743 15
0 744 08
0 745 D5
0 746 76
0 747 AB
0 748 29
0 749 F4
0 750 57
0 751 8A
0 752 6D
0 753 B0
0 754 13
0 755 CE
0 756 4C
0 757 91
0 758 32
0 759 EF
0 760 F2
0 761 2F
0 762 8C
0 763 51
0 764 D3
0 765 0E
0 766 AD
0 767 70
0 768 5D
0 769 80
0 770 25
0 772 FE
0 773 A1
0 774 02
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Ok, so at this point I'm pretty sure that the checksum is an 8 bit crc... The problem now is finding both the correct polynomial and determining the source message data... Which has been difficult at this point... But running software simulations...
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I noticed that values 00, 03, 06, 09 and 0C are missing... this can be only a coincidence... but this can also be a starting point.
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when you are testing CRC's are you removing the odd parity per byte first?
something like this (most leading zeros omitted):
Hex CRC
04000001 63
04000002 0D
04000004 5C
04000007 32
04000008 73
0400000B 1D
0400000D 4C
0400000E 22
04000010 2C
04000013 42
04000015 13
04000016 7D
04000019 3C
0400001A 52
0400001C 03
0400001F 6D
04000020 1E
04000023 70
04000025 21
04000026 4F
04000029 0E
0400002A 60
0400002C 31
0400002F 5F
04000031 51
04000032 3F
04000034 6E
04000037 00
04000038 41
0400003B 2F
0400003D 7E
0400003E 10
04000040 7B
04000043 15
04000045 44
04000046 2A
04000049 6B
0400004A 05
0400004C 54
0400004F 3A
04000051 34
04000052 5A
04000054 0B
04000057 65
04000058 24
0400005B 4A
0400005D 1B
0400005E 75
04000061 06
04000062 68
04000064 39
04000067 57
04000068 16
0400006B 78
0400006D 29
0400006E 47
04000070 49
04000073 27
04000075 76
04000076 18
04000079 59
0400007A 37
0400007C 66
0400007F 08
04000080 38
04000083 56
04000085 07
04000086 69
04000089 28
0400008A 46
0400008C 17
0400008F 79
04000091 77
04000092 19
04000097 26
04000098 67
0400009B 09
0400009D 58
0400009E 36
040000A1 45
040000A2 2B
040000A4 7A
040000A7 14
040000A8 55
040000AB 3B
040000AD 6A
040000AE 04
040000B0 0A
040000B3 64
040000B5 35
040000B6 5B
040000B9 1A
040000BA 74
040000BC 25
040000BF 4B
040000C1 20
040000C2 21
040000C4 1F
040000C7 71
040000C8 30
040000CB 5E
040000CD 0F
040000CE 61
040000D0 6F
040000D3 01
040000D5 50
040000D6 3E
040000DA 7F
040000DC 40
040000DF 2E
040000E0 5D
040000E3 33
040000E5 62
040000E6 0C
040000E9 4D
040000EA 23
040000EC 72
040000EF 1C
040000F1 12
040000F2 7C
040000F4 2D
040000F7 2E
040000F8 02
040000FB 6C
040000FD 3D
040000FE 53
04000100 6D
04000105 52
04000106 3C
04000109 7D
0400010A 13
0400010C 42
0400010F 43
04000111 22
04000112 4C
04000114 1D
04000117 73
04000118 32
0400011B 5C
0400011D 0D
0400011E 63
04000121 10
04000127 41
04000128 00
0400012B 6E
0400012D 3F
0400012E 51
04000130 5F
04000133 31
04000135 60
04000136 0E
04000139 4F
0400013A 21
0400013C 70
0400013F 1E
04000141 1F
04000142 1B
04000144 4A
04000147 24
04000148 65
0400014B 0B
0400014D 5A
0400014E 34
04000150 3A
04000153 54
04000155 05
04000156 6B
04000159 2A
0400015A 44
0400015C 15
0400015F 7B
04000160 7C
04000163 66
04000165 37
04000169 18
0400016A 76
0400016C 27
0400016F 49
04000171 47
04000172 29
04000174 78
04000177 16
04000178 57
0400017B 39
0400017D 68
0400017E 06
04000181 36
04000182 58
04000184 09
04000187 67
04000188 26
0400018B 48
0400018D 19
0400018E 77
04000190 79
04000193 17
04000195 46
04000196 28
04000199 69
0400019A 07
0400019C 56
0400019F 38
040001A0 4B
040001A3 25
040001A5 74
040001A6 1A
040001A9 5B
040001AA 35
040001AC 64
040001B1 04
040001B2 6A
040001B4 3B
040001B7 55
040001B8 14
040001BB 7A
040001BD 2B
040001BE 45
040001C0 2E
040001C3 40
040001C5 11
040001C9 7F
040001CA 50
040001CC 01
040001CF 6F
040001D1 61
040001D2 0F
040001D4 10
040001D7 30
040001D8 71
040001DB 1F
040001DD 4E
040001DE 20
040001E1 53
040001E2 3D
040001E4 6C
040001E7 02
040001E8 43
040001EB 2D
040001ED 7C
040001EE 12
040001F0 1C
040001F3 72
040001F5 23
040001F6 4D
040001F9 0C
040001FA 62
040001FC 33
040001FF 5D
04000200 4B
04000203 25
04000205 74
04000206 1A
04000209 5B
0400020A 35
0400020C 64
0400020F 0A
04000211 04
04000212 6A
04000214 3B
04000217 55
04000218 14
0400021B 7A
0400021D 2C
0400021E 45
04000221 36
04000222 58
04000224 09
04000227 67
04000228 26
0400022B 48
0400022D 19
0400022E 77
04000230 79
04000235 46
04000236 28
04000239 6A
0400023A 07
0400023C 56
0400023F 38
04000241 53
04000242 3D
04000247 02
04000248 43
0400024B 2D
0400024D 7C
0400024E 12
04000250 1C
04000253 72
04000255 23
04000256 4D
04000259 0C
0400025A 62
0400025C 33
0400025F 5D
04000260 2F
04000263 40
04000265 11
04000269 7F
0400026A 50
0400026C 01
0400026F 6F
04000271 61
04000272 0F
04000274 5E
04000277 30
04000278 71
0400027B 1F
0400027D 4E
0400027E 4F
04000281 10
04000282 7E
04000284 2F
04000287 41
04000288 00
0400028B 6E
0400028D 3F
0400028E 51
04000290 5F
04000293 31
04000295 60
04000296 0E
04000299 4F
0400029A 21
0400029C 70
0400029F 1E
040002A0 6D
040002A3 03
040002A5 52
040002A6 3C
040002A9 7D
040002AA 13
040002AF 2C
040002B1 22
040002B2 4C
040002B4 1E
040002B7 73
040002B8 32
040002BB 5C
040002BD 0D
040002BE 63
040002C0 08
040002C3 66
040002C5 37
040002C6 59
040002C9 18
040002CA 76
040002CC 27
040002CF 49
040002D1 47
040002D4 78
040002D7 16
040002D8 17
040002DB 39
040002DD 68
040002DE 06
040002E1 75
040002E2 1B
040002E4 4A
040002E7 24
040002E8 65
040002EB 0B
040002ED 5A
040002EE 34
040002F0 3A
040002F3 54
040002F5 05
040002F6 6B
040002F9 2A
040002FA 44
040002FC 15
040002FF 7B
04000301 45
04000302 2B
04000304 7A
04000307 14
04000308 55
0400030B 3B
0400030D 6A
0400030E 04
04000310 0A
04000313 64
04000315 35
04000316 5B
04000319 1A
0400031A 74
0400031C 25
0400031F 4B
04000320 38
04000323 56
04000325 07
04000326 69
04000329 28
0400032A 46
0400032C 17
0400032F 79
04000331 77
04000332 19
04000334 48
04000337 26
04000338 67
0400033B 09
0400033D 58
0400033E 59
04000340 5D
04000343 33
04000345 62
04000346 0C
04000349 4D
0400034A 23
0400034C 72
0400034F 1C
04000351 12
04000352 7C
04000354 2D
04000357 43
04000358 44
0400035B 6C
0400035D 3D
0400035E 53
04000361 20
04000362 4E
04000364 1F
04000367 71
04000368 30
0400036B 5E
0400036D 0F
0400036E 61
04000370 6F
04000373 01
04000375 50
04000376 3E
04000379 3F
0400037A 11
0400037F 2E
04000380 1E
04000383 70
04000385 21
04000386 4F
04000389 0E
0400038A 60
0400038C 31
0400038F 5F
04000391 60
04000392 3F
04000394 6E
04000397 00
04000398 01
0400039B 2F
0400039D 7E
0400039E 10
040003A1 63
040003A2 0D
040003A4 5C
040003A7 32
040003A8 73
040003AB 1D
040003AD 4C
040003AE 22
040003B0 2C
040003B3 42
040003B5 13
040003B6 7D
040003B9 3C
040003BA 52
040003BC 03
040003BF 6D
040003C1 06
040003C2 68
040003C4 39
040003C7 57
040003C8 16
040003CB 78
040003CD 29
040003CE 2A
040003D0 49
040003D3 4A
040003D5 76
040003D6 18
040003D9 59
040003DA 37
040003DC 66
040003DF 08
040003E0 7B
040003E3 15
040003E6 2A
040003E9 2B
040003EA 05
040003EC 54
040003EF 3A
040003F1 34
040003F2 5A
040003F4 5B
040003F7 65
040003F8 24
040003FB 4A
040003FE 75
04000400 06
04000403 68
04000405 39
04000406 57
04000409 16
0400040A 78
0400040C 29
0400040F 47
04000412 27
04000414 76
04000417 18
04000418 59
0400041B 37
0400041D 66
0400041E 08
04000421 7B
04000422 15
04000424 44
04000427 2A
04000428 6B
0400042B 05
0400042D 54
0400042E 3A
04000430 34
04000433 5A
04000435 0B
04000436 65
04000439 24
0400043A 4A
0400043C 1B
0400043F 75
04000441 1E
04000442 70
04000444 21
04000447 4F
04000448 0E
0400044B 60
0400044D 31
0400044E 5F
04000450 51
04000453 3F
04000455 6E
04000456 00
04000459 41
0400045A 2F
0400045C 7E
0400045F 10
04000460 64
04000463 0D
04000465 5C
04000466 32
04000469 73
0400046A 1D
0400046C 4C
0400046F 22
04000471 2C
04000472 42
04000474 13
04000477 7D
04000478 3C
0400047B 52
0400047D 03
0400047E 6D
04000481 5D
04000482 33
04000484 62
04000487 0C
04000488 4D
0400048B 23
0400048D 72
0400048E 1C
04000490 12
04000493 7C
04000495 2D
04000496 43
04000499 02
0400049A 6C
0400049C 3D
0400049F 53
040004A0 20
040004A3 4E
040004A5 1F
040004A6 71
040004A9 30
040004AA 5E
040004AC 0F
040004AF 61
040004B1 6F
040004B2 01
040004B4 50
040004B7 3E
040004BB 7F
040004BD 40
040004BE 2E
040004C0 45
040004C3 2B
040004C6 14
040004C9 55
040004CA 3B
040004CC 6A
040004CF 04
040004D1 0A
040004D2 64
040004D4 35
040004D7 5B
040004D8 1A
040004DB 75
040004DD 25
040004DE 4B
040004E1 38
040004E2 56
040004E4 07
040004E7 69
040004E8 28
040004EB 46
040004ED 17
040004EE 79
040004F0 77
040004F3 19
040004F5 48
040004F6 26
040004F9 67
040004FA 09
040004FC 58
040004FF 36
04000501 08
04000502 66
04000504 37
04000507 59
04000508 18
0400050B 76
0400050D 27
0400050E 49
04000510 47
04000513 29
04000515 78
04000516 16
04000519 57
0400051A 3A
0400051C 68
0400051F 06
04000520 75
04000523 1B
04000525 4A
04000526 24
04000529 65
0400052A 0B
0400052C 5A
0400052F 34
04000531 3A
04000532 54
04000534 05
04000537 6B
04000538 2A
0400053B 44
0400053D 15
0400053E 7C
04000540 10
04000543 7E
04000545 2F
04000546 41
04000549 00
0400054A 6E
0400054C 3F
0400054F 51
04000551 5F
04000552 31
04000554 60
04000557 0E
04000558 4F
0400055B 21
0400055D 70
0400055E 1E
04000561 6D
04000562 03
04000564 52
04000567 3C
04000568 7D
0400056B 13
0400056D 42
0400056E 2C
04000570 22
04000573 4C
04000575 1D
04000576 74
04000579 32
0400057A 5C
0400057C 0D
0400057F 63
04000580 53
04000583 3D
04000585 6C
04000586 02
04000589 43
0400058A 2D
0400058C 7C
0400058F 12
04000591 1C
04000592 72
04000594 23
04000597 4D
04000598 0C
0400059B 62
0400059D 33
0400059E 5D
040005A1 2E
040005A2 40
040005A4 11
040005A8 7F
040005AB 50
040005AD 01
040005AE 6F
040005B0 61
040005B3 0F
040005B5 5E
040005B6 30
040005B9 71
040005BA 1F
040005BC 4E
040005BF 20
040005C1 4B
040005C2 25
040005C4 74
040005C7 1A
040005C8 5B
040005CB 35
040005CD 64
040005CE 0A
040005D0 04
040005D3 6A
040005D5 3B
040005D6 55
040005D9 14
040005DA 7A
040005DC 2B
040005DF 45
040005E0 36
040005E3 58
040005E5 09
040005E6 67
040005E9 26
040005EA 48
040005EC 19
040005EF 77
040005F1 79
040005F2 17
040005F4 46
040005F7 28
040005F8 69
040005FB 07
040005FD 56
040005FE 38
04000601 2E
04000602 40
04000604 12
04000608 7F
0400060B 50
0400060D 01
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when you are testing CRC's are you removing the odd parity per byte first?
something like this (most leading zeros omitted):
Sir, I am not clear on your question. The checksum byte that I provided includes the odd parity bit that is present at the LSB position. The found checksum is the upper 7 bits of the byte provided. I am sure that this is CRC8, but don't know what the original message is or the binomial that it's calculated with.
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I'm pretty sure that the general method for computing the checksum in the Farpointe format is given in this patent number US 6411199 B1
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hkplus, thanks for your contributions.
Do you have ICQ where you can be contacted at?
Thanks!
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14011746
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Well, I tried it against these known 8bit crc, none fits.
name="CRC-8/DVB-S2"
name="CRC-8/CDMA2000"
name="CRC-8/I-CODE"
name="CRC-8/ITU"
name="CRC-8"
name="CRC-8/WCDMA"
name="CRC-8/DARC"
name="CRC-8/MAXIM"
name="CRC-8/EBU"
name="CRC-8/ROHC"
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