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0280: hamming_decode_hl: Hamming 8/4 decode the byte at address in HL and return it in B.
Used by the routines at NMI_ISR, decode_magazine_number and decode_packet_number.
hamming_decode_hl 0280 LD C,(HL) Read byte at address in HL into C.
0281 PUSH HL Add to hamming_decode_table_pointer to get offset in table.
0282 LD HL,(hamming_decode_table_pointer)
0285 LD B,$00
0287 ADD HL,BC
0288 LD B,(HL) Return decoded byte from table in B.
0289 POP HL
exit_pointer_RET 028A RET This RET instruction is used to return from menus, vectored through exit_pointer.
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