|
Routines |
| Prev: 37718 | Up: Map | Next: 37798 |
|
Scan the six alien slots at Alien_Slot_1 and return the first unused one.
|
||||||||||||
|
Scan the six alien slots and return the first free one.
|
||||||||||||
| FindSlotAlien | 37781 | LD HL,25008 | HL=Alien_Slot_1. | |||||||||
|
There are a maximum of 6 aliens on screen at a time.
|
||||||||||||
| 37784 | LD B,6 | Set an alien slot counter in B for 6 loops. | ||||||||||
| 37786 | LD DE,24 | DE=0024 (the length of each slot). | ||||||||||
| FindSlotAlien_Loop | 37789 | LD A,(HL) | Jump to FindSlotAlien_Return if this slot is unused. | |||||||||
| 37790 | AND A | |||||||||||
| 37791 | JR Z,FindSlotAlien_Return | |||||||||||
| 37793 | ADD HL,DE | Move onto the next slot. | ||||||||||
| 37794 | DJNZ FindSlotAlien_Loop | Decrease the alien counter by one and loop back to FindSlotAlien_Loop until every slot has been checked. | ||||||||||
| 37796 | AND A | Leave the Z flag unset as no free slot was found. | ||||||||||
| FindSlotAlien_Return | 37797 | RET | Return. | |||||||||
| Prev: 37718 | Up: Map | Next: 37798 |