Routines
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E475: Set Home To Default Attributes
Used by the routine at DEED.
Home_DefaultAttributes E475 LD DE,$5822 DE=5822 (attribute buffer location).
E478 LD HL,$E4AE HL=HomeAttributes.
The home block is 04x04 (04 rows of 04 bytes) but not all of it cycles attributes. Only 03x04 is used here.
E47B LD B,$04 Set a counter in B for 04 rows.
Home_DefaultAttributes_Loop E47D PUSH BC Stash the row counter on the stack.
E47E LD BC,$0003 Copy 0003 bytes from the attribute buffer to HomeAttributes.
E481 LDIR
One full row is 20 bytes, so this is 03 bytes less than one row. Hence this moves down one row, but back to the start of the line.
E483 EX DE,HL Add 001D to the attribute buffer position.
E484 LD BC,$001D
E487 ADD HL,BC
E488 EX DE,HL
E489 POP BC Restore the row counter from the stack.
E48A DJNZ Home_DefaultAttributes_Loop Decrease the row counter by one and loop back to Home_DefaultAttributes_Loop until all the rows have been updated.
E48C RET Return.
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