| Routines

8944: Display the game over sequence

Used by the routine at 870E. First check whether we have a new high score.
8944 | LD HL,$841F | Point HL at the high score at 841F
8947 | LD DE,$8429 | Point DE at the current score at 8429
894A | LD B,$06 | There are 6 digits to compare
894C | LD A,(DE) | Pick up a digit of the current score
894D | CP (HL) | Compare it with the corresponding digit of the high score
894E | JP C,$8963 | Jump if it's less than the corresponding digit of the high score
8951 | JP NZ,$8958 | Jump if it's greater than the corresponding digit of the high score
8954 | INC HL | Point HL at the next digit of the high score
8955 | INC DE | Point DE at the next digit of the current score
8956 | DJNZ $894C | Jump back to compare the next pair of digits
8958 | LD HL,$8429 | Replace the high score with the current score
895B | LD DE,$841F
895E | LD BC,$0006
8961 | LDIR
Now prepare the screen for the game over sequence.
8963 | LD HL,$4000 | Clear the top two-thirds of the display file
8966 | LD DE,$4001
8969 | LD BC,$0FFF
896C | LD (HL),$00
896E | LDIR
8970 | XOR A | Initialise the game status buffer variable at 80DC; this variable will determine the distance of the boot from the top of the screen
8971 | LD ($80DC),A
8974 | LD DE,$8240 | Draw Willy at (12,15)
8977 | LD HL,$488F
897A | LD C,$00
897C | CALL $8FF4
897F | LD DE,$B6E0 | Draw the plinth (see B6E0) underneath Willy at (14,15)
8982 | LD HL,$48CF
8985 | LD C,$00
8987 | CALL $8FF4
The following loop draws the boot's descent onto the plinth that supports Willy while producing a sound effect. Your browser doesn't support HTML5 audio. Here is a link to the audio instead.
898A | LD A,($80DC) | Pick up the distance variable from 80DC
898D | LD C,A | Point BC at the corresponding entry in the screen buffer address lookup table at 8300
898E | LD B,$83
8990 | LD A,(BC) | Point HL at the corresponding location in the display file
8991 | OR $0F
8993 | LD L,A
8994 | INC BC
8995 | LD A,(BC)
8996 | SUB $20
8998 | LD H,A
8999 | LD DE,$BAE0 | Draw the boot (see BAE0) at this location, without erasing the boot at the previous location; this leaves the portion of the boot sprite that's above the ankle in place, and makes the boot appear as if it's at the end of a long, extending trouser leg
899C | LD C,$00
899E | CALL $8FF4
89A1 | LD A,($80DC) | Pick up the distance variable from 80DC
89A4 | CPL | A=0xFF-A
89A5 | LD E,A | Store this value (0x3F-0xFF) in E; it determines the (rising) pitch of the sound effect that will be made
89A6 | XOR A | A=0 (black border)
89A7 | LD BC,$0040 | C=0x40; this value determines the duration of the sound effect
89AA | OUT ($FE),A | Produce a short note whose pitch is determined by E
89AC | XOR $18
89AE | LD B,E
89AF | DJNZ $89AF
89B1 | DEC C
89B2 | JR NZ,$89AA
89B4 | LD HL,$5800 | Prepare BC, DE and HL for setting the attribute bytes in the top two-thirds of the screen
89B7 | LD DE,$5801
89BA | LD BC,$01FF
89BD | LD A,($80DC) | Pick up the distance variable from 80DC
89C0 | AND $0C | Keep only bits 2 and 3
89C2 | RLCA | Shift bits 2 and 3 into bits 3 and 4; these bits determine the PAPER colour: 0, 1, 2 or 3
89C3 | OR $47 | Set bits 0-2 (INK 7) and 6 (BRIGHT 1)
89C5 | LD (HL),A | Copy this attribute value into the top two-thirds of the screen
89C6 | LDIR
89C8 | LD A,($80DC) | Add 4 to the distance variable at 80DC; this will move the boot sprite down two pixel rows
89CB | ADD A,$04
89CD | LD ($80DC),A
89D0 | CP $C4 | Has the boot met the plinth yet?
89D2 | JR NZ,$898A | Jump back if not
Now print the "Game Over" message, just to drive the point home.
89D4 | LD IX,$844F | Print "Game" (see 844F) at (6,10)
89D8 | LD C,$04
89DA | LD DE,$40CA
89DD | CALL $92BA
89E0 | LD IX,$8453 | Print "Over" (see 8453) at (6,18)
89E4 | LD C,$04
89E6 | LD DE,$40D2
89E9 | CALL $92BA
89EC | LD BC,$0000 | Prepare the delay counters for the following loop; the counter in C will also determine the INK colours to use for the "Game Over" message
89EF | LD D,$06
The following loop makes the "Game Over" message glisten for about 1.57s.
89F1 | DJNZ $89F1 | Delay for about a millisecond
89F3 | LD A,C | Change the INK colour of the "G" in "Game" at (6,10)
89F4 | AND $07
89F6 | OR $40
89F8 | LD ($58CA),A
89FB | INC A | Change the INK colour of the "a" in "Game" at (6,11)
89FC | AND $07
89FE | OR $40
8A00 | LD ($58CB),A
8A03 | INC A | Change the INK colour of the "m" in "Game" at (6,12)
8A04 | AND $07
8A06 | OR $40
8A08 | LD ($58CC),A
8A0B | INC A | Change the INK colour of the "e" in "Game" at (6,13)
8A0C | AND $07
8A0E | OR $40
8A10 | LD ($58CD),A
8A13 | INC A | Change the INK colour of the "O" in "Over" at (6,18)
8A14 | AND $07
8A16 | OR $40
8A18 | LD ($58D2),A
8A1B | INC A | Change the INK colour of the "v" in "Over" at (6,19)
8A1C | AND $07
8A1E | OR $40
8A20 | LD ($58D3),A
8A23 | INC A | Change the INK colour of the "e" in "Over" at (6,20)
8A24 | AND $07
8A26 | OR $40
8A28 | LD ($58D4),A
8A2B | INC A | Change the INK colour of the "r" in "Over" at (6,21)
8A2C | AND $07
8A2E | OR $40
8A30 | LD ($58D5),A
8A33 | DEC C | Decrement the counter in C
8A34 | JR NZ,$89F1 | Jump back unless it's zero
8A36 | DEC D | Decrement the counter in D (initially 6)
8A37 | JR NZ,$89F1 | Jump back unless it's zero
8A39 | JP $85CC | Display the title screen and play the theme tune