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Routine $0206:   "M-W" command body, decrypt [$0300-$0380] code area

Memory commands ("M-W", "M-E") are cached in the 1541 [$0200-$0229]
"Buffer for command string", starting at $0200 for each command. The "M-E"
command was 5 bytes long and overwrote the first 5 bytes of the "M-W" command
which are no longer needed as the "M-W" command was already executed
($15 data bytes copied to [$B5-$C9]). So the body of the "M-W" command
remains at $0206-$0217: our routine here. This routine enables Interrupts
again but Job #4's execution is not enforced here. Then [$0300-$0380] is
decrypted and executed.
	
Jump from $07FD:

0206: 58        CLI            ; enable Interrupts for executing Job #4 (read Sector 3 to [$07xx])
0207: 49 36     EOR #$36       ; XOR with parity of last read data buffer (Sector 15), should be $35
0209: 85 06     STA $06        ; [$06]:= ($35 xor $36) = #$03, so [$05/$06] points to $0300

Jump from $0213:

020B: B1 05     LDA ($05),Y
020D: 59 17 04  EOR $0417,Y
0210: 91 05     STA ($05),Y    ; decryption, [$0300-$0380]:= [$0300-$0380] xor [$0417-$0497]
0212: 88        DEY
0213: 10 F6     BPL $020B

0215: 6C 05 00  JMP ($0005)    ; jump to $0300 (see above $0209 statement)

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