Routines
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03137: 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 03137 PUSH AF Save the 'entry number'.
03138 EX DE,HL HL now holds the base address.
03139 INC A Compensate for the 'DEC A' below.
PO_STEP 03140 BIT 7,(HL) Wait for an 'inverted character'.
03142 INC HL
03143 JR Z,PO_STEP
03145 DEC A Count through the entries until the correct one is found.
03146 JR NZ,PO_STEP
03148 EX DE,HL DE points to the initial character.
03149 POP AF Fetch the 'entry number' and return with carry set for the first thirty two entries.
03150 CP 32
03152 RET C
03153 LD A,(DE) However if the initial character is a letter then a leading space may be needed.
03154 SUB "A"
03156 RET
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