| ← A938 | Map | A99A → |
A954: Hold a ball on the bat, and release it
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Holds a ball on the bat until fire, a release request, or 250 frames. When a ball arrives at the bat, the bat catches it only while the glue prize is active.
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A ball parked for a serve is held the same way. The serve setup raises its stuck flag, so from its first frame it takes the held branch whether or not glue is active. The serve comes on fire or on a release request, and otherwise by itself after 250 frames.
Only a glue catch and the level setup clear the hold timer, and the promotion of ball B copies its timer over ball A's. A release leaves the timer where it stands, so a serve after a lost ball resumes that count. After a fire release the serve comes that much sooner. After a timeout release the count runs through the wrap, so it takes 256 frames.
The hold timer, the release request and the fire press are each checked every frame while the ball is held.
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| ball_catch_test | A954 | LD A,(IY+$0B) | Not already stuck to the bat? Handle the ball's arrival. | ||||||||
| A957 | OR A | ||||||||||
| A958 | JR Z,catch_on_arrival | ||||||||||
| A95A | INC (IY+$0F) | Held: advance the hold timer. | |||||||||
| A95D | LD A,(IY+$0F) | ||||||||||
| A960 | CP $FA | Release once the hold timer runs out. | |||||||||
| A962 | JR Z,catch_release | ||||||||||
| A964 | LD A,(glue_release_req) | Release if a new prize has requested it. | |||||||||
| A967 | OR A | ||||||||||
| A968 | JR NZ,catch_release | ||||||||||
| A96A | LD HL,controls | Release on a fire press; otherwise hold the ball. | |||||||||
| A96D | BIT 4,(HL) | ||||||||||
| A96F | JR Z,catch_stay_held | ||||||||||
| catch_release | A971 | XOR A | Release: clear the request latch and the caught flag, and report a bounce. | ||||||||
| A972 | LD (glue_release_req),A | ||||||||||
| A975 | LD (IY+$0B),A | ||||||||||
| A978 | INC A | ||||||||||
| A979 | RET | ||||||||||
| catch_on_arrival | A97A | LD A,(glue_active) | A fresh arrival: catch the ball only while the glue prize is active. | ||||||||
| A97D | OR A | ||||||||||
| A97E | JR NZ,catch_hold_ball | ||||||||||
| A980 | XOR A | Glue off: clear the request latch and report a normal bounce. | |||||||||
| A981 | LD (glue_release_req),A | ||||||||||
| A984 | INC A | ||||||||||
| A985 | RET | ||||||||||
| catch_hold_ball | A986 | LD A,$01 | Catch the ball: set the caught flag. | ||||||||
| A988 | LD (IY+$0B),A | ||||||||||
| A98B | XOR A | Freeze it on the bat: zero both step thresholds. | |||||||||
| A98C | LD (IY+$02),A | ||||||||||
| A98F | LD (IY+$03),A | ||||||||||
| A992 | LD (IY+$0F),A | Restart the hold timer. | |||||||||
| catch_stay_held | A995 | XOR A | Held this frame: clear the request latch and report no bounce. | ||||||||
| A996 | LD (glue_release_req),A | ||||||||||
| A999 | RET | ||||||||||
| ← A938 | Map | A99A → |