proxmark3 read write block0 of uid changeable mifare card

proxmark3> hf mf rdbl 0 a ffffffffffff
--block no:0, key type:A, key:ff ff ff ff ff ff
#db# READ BLOCK FINISHED
isOk:01 data:04 89 75 c7 3f 88 04 00 c1 85 14 98 5d 30 34 12
proxmark3> hf 14a reader
ATQA : 00 04
 UID : d4 5e 63 06
 SAK : 08 [2]
TYPE : NXP MIFARE CLASSIC 1k | Plus 2k SL1
proprietary non iso14443-4 card found, RATS not supported
Answers to chinese magic backdoor commands: YES
proxmark3> hf mf cgetblk 0
--block number: 0
block data:d4 5e 63 06 ef 08 04 00 12 13 14 15 16 17 18 19
proxmark3> hf mf csetblk 0 048975c73f880400c18514985d303412
--block number: 0 data:04 89 75 c7 3f 88 04 00 c1 85 14 98 5d 30 34 12

proxmark3> hf mf cgetblk 0
--block number: 0
block data:04 89 75 c7 3f 88 04 00 c1 85 14 98 5d 30 34 12
proxmark3>

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