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Routines |
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Used by the routine at StartPictureModeScreenIdle.
Jumps to MatchCharacterPair when the command mode at 40996 is 2. Otherwise walks the clause in E and stores the words it accepts.
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| CheckDisplayMode | 43921 | LD A,(40996) | Jump to MatchCharacterPair if the command mode at 40996 is 2. | |
| 43924 | CP 2 | |||
| 43926 | JR Z,MatchCharacterPair | |||
| 43928 | LD A,E | Read the low byte of the source. | ||
| 43929 | OR 7 | Mark bits 0-2 on the result. | ||
| 43931 | LD E,A | Store the result in the low byte of the source. | ||
| CheckDisplayMode_Loop | 43932 | CALL SaveTextPointer | Go to CheckDisplayMode_Loop if it is 224. | |
| 43935 | CP 224 | |||
| 43937 | JR Z,CheckDisplayMode_Loop | |||
| 43939 | CP 48 | Go to CheckDisplayMode_Next if it is not 48. | ||
| 43941 | JR NZ,CheckDisplayMode_Next | |||
| CheckDisplayMode_TestBitClear | 43943 | BIT 1,E | Jump ahead to CheckDisplayMode_ConditionHoldsCaller if bit 1 is clear. | |
| 43945 | JR Z,CheckDisplayMode_ConditionHoldsCaller | |||
| CheckDisplayMode_CharacterLowByte | 43947 | RES 1,E | Clear bit 1 of E and store BC at IY+0-1. | |
| 43949 | LD (IY+0),C | |||
| 43952 | LD (IY+1),B | |||
| 43955 | 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 | 43957 | SCF | Mark the condition as met. | |
| 43958 | 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 | 43959 | CP 0 | Go to CheckDisplayMode_TestCodeClearsFirst if it is not 0. | |
| 43961 | JR NZ,CheckDisplayMode_TestCodeClearsFirst | |||
| CheckDisplayMode_TestBitClearAgain | 43963 | BIT 2,E | Jump back to CheckDisplayMode_ConditionHoldsCaller if bit 2 is clear. | |
| 43965 | JR Z,CheckDisplayMode_ConditionHoldsCaller | |||
| 43967 | RES 2,E | Clear bit 2 of E and store BC at IY+2-3. | ||
| 43969 | LD (IY+2),C | |||
| 43972 | LD (IY+3),B | |||
| 43975 | JR CheckDisplayMode_Loop | Go back and test the next display marker. | ||
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A code of 64 clears the first flag bit.
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| CheckDisplayMode_TestCodeClearsFirst | 43977 | CP 64 | Go to CheckDisplayMode_TestBlankKeepsSecond unless the code is 64. | |
| 43979 | JR NZ,CheckDisplayMode_TestBlankKeepsSecond | |||
| 43981 | RES 0,E | Clear the mark on this character. | ||
| 43983 | 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 | 43985 | CP 32 | Go to CheckDisplayMode_TestDisplayModeZero if it is not 32. | |
| 43987 | JR NZ,CheckDisplayMode_TestDisplayModeZero | |||
| 43989 | BIT 1,E | Jump back to CheckDisplayMode_TestBitClear while bit 1 is present. | ||
| 43991 | JR NZ,CheckDisplayMode_TestBitClear | |||
| 43993 | BIT 0,E | Jump back to CheckDisplayMode_TestBitClearAgain while bit 0 is present. | ||
| 43995 | JR NZ,CheckDisplayMode_TestBitClearAgain | |||
| 43997 | RES 2,E | Clear the mark on this character, then set the mark on this character. | ||
| 43999 | SET 0,E | |||
| 44001 | LD A,(IY+0) | |||
| 44004 | LD (IY+2),A | Store A at IY+2. | ||
| 44007 | LD A,(IY+1) | Copy the high byte beside the low byte and repeat the store from CheckDisplayMode_CharacterLowByte. | ||
| 44010 | LD (IY+3),A | |||
| 44013 | 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 | 44015 | OR A | See whether the display mode is zero. | |
| 44016 | BIT 1,E | See whether bit 1 of the low byte of the source is set. | ||
| 44018 | RET | Return. | ||
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