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Routines |
| Prev: AB52 | Up: Map | Next: ABF3 |
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Used by the routine at StartPictureModeScreenIdle.
Jumps to MatchCharacterPair when the command mode at A024 is 02. Otherwise walks the clause in E and stores the words it accepts.
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| CheckDisplayMode | AB91 | LD A,($A024) | Jump to MatchCharacterPair if the command mode at A024 is 02. | |
| AB94 | CP $02 | |||
| AB96 | JR Z,MatchCharacterPair | |||
| AB98 | LD A,E | Read the low byte of the source. | ||
| AB99 | OR $07 | Mark bits 0-2 on the result. | ||
| AB9B | LD E,A | Store the result in the low byte of the source. | ||
| CheckDisplayMode_Loop | AB9C | CALL SaveTextPointer | Go to CheckDisplayMode_Loop if it is E0. | |
| AB9F | CP $E0 | |||
| ABA1 | JR Z,CheckDisplayMode_Loop | |||
| ABA3 | CP $30 | Go to CheckDisplayMode_Next if it is not 30. | ||
| ABA5 | JR NZ,CheckDisplayMode_Next | |||
| CheckDisplayMode_TestBitClear | ABA7 | BIT 1,E | Jump ahead to CheckDisplayMode_ConditionHoldsCaller if bit 1 is clear. | |
| ABA9 | JR Z,CheckDisplayMode_ConditionHoldsCaller | |||
| CheckDisplayMode_CharacterLowByte | ABAB | RES 1,E | Clear bit 1 of E and store BC at IY+00-01. | |
| ABAD | LD (IY+$00),C | |||
| ABB0 | LD (IY+$01),B | |||
| ABB3 | JR CheckDisplayMode_Loop | Go back and test the next display marker. | ||
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The condition holds, so the caller continues.
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| CheckDisplayMode_ConditionHoldsCaller | ABB5 | SCF | Mark the condition as met. | |
| ABB6 | RET | Return. | ||
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A zero code clears the third flag bit when that bit is set.
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| CheckDisplayMode_Next | ABB7 | CP $00 | Go to CheckDisplayMode_TestCodeClearsFirst if it is not 00. | |
| ABB9 | JR NZ,CheckDisplayMode_TestCodeClearsFirst | |||
| CheckDisplayMode_TestBitClearAgain | ABBB | BIT 2,E | Jump back to CheckDisplayMode_ConditionHoldsCaller if bit 2 is clear. | |
| ABBD | JR Z,CheckDisplayMode_ConditionHoldsCaller | |||
| ABBF | RES 2,E | Clear bit 2 of E and store BC at IY+02-03. | ||
| ABC1 | LD (IY+$02),C | |||
| ABC4 | LD (IY+$03),B | |||
| ABC7 | JR CheckDisplayMode_Loop | Go back and test the next display marker. | ||
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A code of 40 clears the first flag bit.
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| CheckDisplayMode_TestCodeClearsFirst | ABC9 | CP $40 | Go to CheckDisplayMode_TestBlankKeepsSecond unless the code is 40. | |
| ABCB | JR NZ,CheckDisplayMode_TestBlankKeepsSecond | |||
| ABCD | RES 0,E | Clear the mark on this character. | ||
| ABCF | JR CheckDisplayMode_TestBitClear | |||
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A blank keeps the second flag bit, or the first when the second is clear.
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| CheckDisplayMode_TestBlankKeepsSecond | ABD1 | CP $20 | Go to CheckDisplayMode_TestDisplayModeZero if it is not 20. | |
| ABD3 | JR NZ,CheckDisplayMode_TestDisplayModeZero | |||
| ABD5 | BIT 1,E | Jump back to CheckDisplayMode_TestBitClear while bit 1 is present. | ||
| ABD7 | JR NZ,CheckDisplayMode_TestBitClear | |||
| ABD9 | BIT 0,E | Jump back to CheckDisplayMode_TestBitClearAgain while bit 0 is present. | ||
| ABDB | JR NZ,CheckDisplayMode_TestBitClearAgain | |||
| ABDD | RES 2,E | Clear the mark on this character, then set the mark on this character. | ||
| ABDF | SET 0,E | |||
| ABE1 | LD A,(IY+$00) | |||
| ABE4 | LD (IY+$02),A | Store A at IY+02. | ||
| ABE7 | LD A,(IY+$01) | Copy the high byte beside the low byte and repeat the store from CheckDisplayMode_CharacterLowByte. | ||
| ABEA | LD (IY+$03),A | |||
| ABED | JR CheckDisplayMode_CharacterLowByte | |||
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See whether the display mode is zero, then see whether bit 1 of the low byte of the source is set.
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| CheckDisplayMode_TestDisplayModeZero | ABEF | OR A | See whether the display mode is zero. | |
| ABF0 | BIT 1,E | See whether bit 1 of the low byte of the source is set. | ||
| ABF2 | RET | Return. | ||
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