Routines |
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This subroutine has two distinct functions.
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EACH_STMT | 198B | LD ($5C5D),HL | Set CH-ADD to the current byte. | |||||||||||||||||
198E | LD C,$00 | Set a 'quotes off' flag. | ||||||||||||||||||
Enter a loop to handle each statement in the BASIC line.
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EACH_S_1 | 1990 | DEC D | Decrease D and return if the required statement has been found. | |||||||||||||||||
1991 | RET Z | |||||||||||||||||||
1992 | RST $20 | Fetch the next character code and jump if it does not match the given token code. | ||||||||||||||||||
1993 | CP E | |||||||||||||||||||
1994 | JR NZ,EACH_S_3 | |||||||||||||||||||
1996 | AND A | But should it match then return with the carry and the zero flags both reset. | ||||||||||||||||||
1997 | RET | |||||||||||||||||||
Now enter another loop to consider the individual characters in the line to find where the statement ends.
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EACH_S_2 | 1998 | INC HL | Update the pointer and fetch the new code. | |||||||||||||||||
1999 | LD A,(HL) | |||||||||||||||||||
EACH_S_3 | 199A | CALL NUMBER | Step over any number. | |||||||||||||||||
199D | LD ($5C5D),HL | Update CH-ADD. | ||||||||||||||||||
19A0 | CP "\"" | Jump forward if the character is not a '"'. | ||||||||||||||||||
19A2 | JR NZ,EACH_S_4 | |||||||||||||||||||
19A4 | DEC C | Otherwise set the 'quotes flag'. | ||||||||||||||||||
EACH_S_4 | 19A5 | CP ":" | Jump forward if the character is a ':'. | |||||||||||||||||
19A7 | JR Z,EACH_S_5 | |||||||||||||||||||
19A9 | CP $CB | Jump forward unless the code is the token 'THEN'. | ||||||||||||||||||
19AB | JR NZ,EACH_S_6 | |||||||||||||||||||
EACH_S_5 | 19AD | BIT 0,C | Read the 'quotes flag' and jump back at the end of each statement (including after 'THEN'). | |||||||||||||||||
19AF | JR Z,EACH_S_1 | |||||||||||||||||||
EACH_S_6 | 19B1 | CP $0D | Jump back unless at the end of a BASIC line. | |||||||||||||||||
19B3 | JR NZ,EACH_S_2 | |||||||||||||||||||
19B5 | DEC D | Decrease the statement counter and set the carry flag before returning. | ||||||||||||||||||
19B6 | SCF | |||||||||||||||||||
19B7 | RET |
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