Routines
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B53D: Print Colour String
Used by the routines at Poem_Start, GameOver_1UP_Messaging and PrintBanner.
Prints a string at the position given, which has its attribute as the first byte. The last character of the string has bit 7 set. The attribute is written to each of the positions of the characters.
Before
colour-string-before
After PrintStringColour
colour-string-after
Input
HL Position of the text, with the Y position in H and the X position in L (both in pixels)
DE Pointer to string data
PrintStringColour B53D PUSH HL Stash the position of the string on the stack.
B53E CALL ScreenAddress Convert the position into a screen address.
B541 LD A,(DE) Fetch the attribute of the string.
B542 EX AF,AF' Stash the attribute in the shadow AF register.
B543 INC DE Move onto the text of the string.
B544 EXX Switch to the shadow registers.
B545 POP HL Restore the position of the string from the stack.
B546 CALL AttributeAddress Convert the position into an attribute address.
This entry point is used by the routine at MenuWriteText.
PrintString_Loop B549 EXX Switch back to the normal registers.
B54A LD A,(DE) Fetch the next character of the string.
B54B BIT 7,A Jump to PrintString_LastCharacter if this is the last character of the string (bit 7 is set).
B54D JR NZ,PrintString_LastCharacter
B54F CALL PrintScreen Print the character.
B552 INC DE Move onto the next character of the string.
B553 EXX Switch to the shadow registers.
B554 EX AF,AF' Fetch the attribute.
B555 LD (HL),A Set the attribute of the character on the screen.
B556 INC L Move onto the next column.
B557 EX AF,AF' Stash the attribute in the shadow AF register.
B558 JR PrintString_Loop Jump back to PrintString_Loop to print the next character.
Because the last character contains the terminator, it needs to be handled separately.
PrintString_LastCharacter B55A AND %01111111 Keep only bits 0-6 (i.e. strip the bit 7 terminator).
B55C CALL PrintScreen Print the last character of the string.
B55F EXX Switch to the shadow registers.
B560 EX AF,AF' Fetch the attribute.
B561 LD (HL),A Set the attribute of the last character on the screen.
B562 RET Return.
View the equivalent code in;
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