Routines
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8479: Pause Check
Used by the routines at GameMenu, Select_Yes/No, PlayerNameInput, Handler_LocationChoice and HighScoreTable.
PauseCheck 8479 LD B,$01 Call 8055 with a count of 01.
847B CALL $8055
847E CALL PauseCheck_Input Call PauseCheck_Input.
8481 JR C,PauseCheck Jump to PauseCheck if the carry flag is set.
Repeat of the above.
8483 LD B,$01 Call 8055 with a count of 01.
8485 CALL $8055
8488 CALL PauseCheck_Input Call PauseCheck_Input.
848B JR C,PauseCheck Jump to PauseCheck if the carry flag is set.
848D RET Return.
Check to see if the SHIFT, Z, X, C, and V keys are being held down.
PauseCheck_Input 848E LD BC,$FEFE Read from the keyboard;
Port Number Bit
0 1 2 3 4
FE SHIFT Z X C V
PauseCheck_Loop 8491 IN A,(C)
8493 AND %00011111 Keep only bits 0-4.
8495 CP $1F Return if A is not equal to 1F (which is ALL of the keys above - 00011111).
8497 RET NZ
8498 RLC B Rotate B left (with carry).
849A JR C,PauseCheck_Loop Jump to PauseCheck_Loop if B has the carry flag set.
849C RET Return.
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