Routines
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29645: Print Character
Used by the routines at DisplayPlayerLives, Score_1UP and PrintString.
Input
A ASCII value to print
HL Screen address
PrintScreen 29645 PUSH BC Stash BC, DE and HL on the stack.
29646 PUSH DE
29647 PUSH HL
29648 LD L,A Create an offset in HL.
29649 LD H,0
29651 ADD HL,HL HL=HL * 8.
29652 ADD HL,HL
29653 ADD HL,HL
29654 LD DE,(23606) DE=CHARS.
29658 ADD HL,DE DE=HL + 15360. For examples of usage;
Letter ASCII Value * 8 (offset) CHARS + offset
"U" 85 680 16040
"L" 76 608 15968
"T" 84 672 16032
"I" 73 584 15944
"M" 77 616 15976
"A" 65 520 15880
"T" 84 672 16032
"E" 69 552 15912
29659 EX DE,HL
Print the character to the screen.
29660 POP HL Restore HL, containing the screen buffer location, from the stack.
This entry point is used by the routine at DisplayPlayerLives.
PrintScreen_0 29661 LD B,8 B=8 (8 rows of pixels).
PrintScreen_Loop 29663 LD A,(DE) Copy a byte from the font data to the screen buffer.
29664 LD (HL),A
29665 INC DE Increment the font data by one.
29666 INC H Move onto the next pixel line.
29667 DJNZ PrintScreen_Loop Decrease counter by one and loop back to PrintScreen_Loop until counter is zero.
29669 POP DE Restore DE and BC from the stack.
29670 POP BC
Reset HL and move to the next column, ready to print the next character.
29671 LD A,H H=H - 8 (reset the display line).
29672 SUB 8
29674 LD H,A
29675 INC L Increment screen column by one.
29676 RET Return.
View the equivalent code in;
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