I can't demod it with manchester clk 8, but the NRZ works well
I'm liking PSK1 better. Once cleaned up a bit, the 2 dumps the OP posted result in:
1: 00000000000000001111111111111111000111111111101011110001101000000111111011111011101111010000001110
2: 00000000000000001111111111111111000101111111101010001110101011111000010111111011101110110000010110
However, looking at the plot for the 2nd dump the data looks questionable, though it does decode reasonably. As the OP has made multiple purchases and reloads it doesn't make a very good A/B comparison.
(Random ramblings: My questions about the system: Does the card store the balance remaining or total loaded + total purchases and makes the machine subtract them to get the remaining balance? Or perhaps both? That could explain the 0.04 difference between the 2 machines. Big endian or little? Scrambled data or clear? Any CRC or parity? As for the machines, do they write the balance back to the card before vending, and if so do they reject the vend if it's unable to? That may make it tricky to clone if it uses a non-standard command set)
The reader is a hole and i don't think a card will work with it !
A round sticker tag on a wooden or plastic rod would probably work better.
Can you post more dumps?
1) Dump the card as it currently is
2) Make 1 (and only 1!) purchase or refill
3) Dump it again
proxmark3> data askedge 28
proxmark3> data rawd am s 8
Found Sequence Terminator - First one is shown by orange and blue graph markers
Using Clock:8, Invert:0, Bits Found:513
ASK/Manchester - Clock: 8 - Decoded bitstream:
0000000000000000
1110100110000010
0000111101100101
0000000001000000
0110100000000000
1110000011100000
0101111000000000
1011000010100000
0000000000000000
0000000000100000
0000000000000000
0000000000100000
0000000000000000
1110100110000010
0000111101100101
0000000001000000
0110100000000000
1110000011100000
0101111000000000
1011000010100000
0000000000000000
0000000000100000
0000000000000000
0000000000100000
0000000000000000
1110100110000010
0000111101100101
0000000001000000
0110100000000000
1110000011100000
0101111000000000
1011000010100000
But as i am not a pro in data demod i can't say what's happend ...
]]>Ok, i have just write a T55 and the demod values are not the same !
did you end up with 7's or did it NOT say that the Sequence Terminator was found?
the data askedge value (28) may not apply for every read. the number may need to be adjusted to get the proper read. (use slider on graph overlay to see what the numbers do)
And you can try reading the t55x7 card with yr pm3 to see if you get the same demod values.
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