Routines
Prev: 714B Up: Map Next: 717B
714C: Check whether a character is immobilised by a blown fuse
Used by the routine at F1FC. Returns with the carry flag set if the character is in an area affected by a blown fuse.
Input
H Character number (0xD7-0xE5)
714C LD L,$04 Point HL at byte 0x04 of the character's buffer
714E BIT 0,(HL) Is the character indoors?
7150 RET Z Return if not
7151 LD L,$01 Point HL at byte 0x01 of the character's buffer
7153 LD A,(HL) A=character's x-coordinate
7154 INC A Point DE at the entry in the table at FFC0 that corresponds to the 8-tile wide column of the play area containing the character
7155 AND $F8
7157 RRA
7158 RRA
7159 RRA
715A ADD A,$C0
715C LD E,A
715D LD D,$FF
715F LD A,(DE) Point DE at the delay counter for the fuse that is in the same building as the character (see 7FA2)
7160 LD E,A
7161 LD D,$7F
7163 LD A,(DE) Pick up the blown fuse delay counter in A
7164 AND A Return with the carry flag reset if there is no fuse here, or the fuse is not currently blown
7165 RET Z
7166 INC L L=0x02
7167 LD A,E A=0xA2-0xA7
7168 LD E,$00 For no. 74 or the hotel, use this y-coordinate for comparison (the roofs of these buildings are inaccessible)
716A CP $A4 Is it the fuse at no. 74 or the hotel?
716C JR C,$7176 Jump if so
716E LD E,$10 For no. 31 or no. 19, use this y-coordinate for comparison (any character on the roof will be unaffected by a blown fuse)
7170 CP $A6 Is it the fuse at no. 31 or no. 19?
7172 JR C,$7176 Jump if so
7174 LD E,$0A For no. 17 or no. 15, use this y-coordinate for comparison (any character on the roof will be unaffected by a blown fuse)
7176 LD A,E A=0 (no. 74 or the hotel), 16 (no. 31 or no. 19), or 10 (no. 17 or no. 15)
7177 CP (HL) Compare this value with the character's y-coordinate
7178 RET C Return with the carry flag set if the character is inside the building (as opposed to on the roof)
7179 XOR A Clear the carry flag
717A RET
Prev: 714B Up: Map Next: 717B