Routines
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0C41: THE 'TABLE SEARCH' SUBROUTINE
Used by the routine at PO_MSG.
Input
A Message table entry number
DE Message table start address
Output
DE Address of the first character of message number A
F Carry flag: suppress (set) or allow (reset) a leading space
PO_SEARCH 0C41 PUSH AF Save the 'entry number'.
0C42 EX DE,HL HL now holds the base address.
0C43 INC A Compensate for the 'DEC A' below.
PO_STEP 0C44 BIT 7,(HL) Wait for an 'inverted character'.
0C46 INC HL
0C47 JR Z,PO_STEP
0C49 DEC A Count through the entries until the correct one is found.
0C4A JR NZ,PO_STEP
0C4C EX DE,HL DE points to the initial character.
0C4D POP AF Fetch the 'entry number' and return with carry set for the first thirty two entries.
0C4E CP $20
0C50 RET C
0C51 LD A,(DE) However if the initial character is a letter then a leading space may be needed.
0C52 SUB "A"
0C54 RET
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