| Routines

05851: THE 'INDEXER' SUBROUTINE

This subroutine is used on several occasions to look through tables.
Input
C | Code to look for
HL | Base address of the table
Output
HL | Address of the second byte of the required table entry (if found)
F | Carry flag is set if the code is found
INDEXER_1 | 05851 | INC HL | Move on to consider the next pair of entries.
The main entry point is here and is used by the routines at CHAN_FLAG, CLOSE_2, OPEN_2, SCANNING and S_LETTER.
INDEXER | 05852 | LD A,(HL) | Fetch the first of a pair of entries but return if it is zero - the end marker.
| 05853 | AND A
| 05854 | RET Z
| 05855 | CP C | Compare it to the supplied code.
| 05856 | INC HL | Point to the second entry.
| 05857 | JR NZ,INDEXER_1 | Jump back if the correct entry has not been found.
| 05859 | SCF | The carry flag is set upon a successful search.
| 05860 | RET |