Knight Tyme (48k): Routine at 54231

54231: Draw a run of characters (e.g. edge of frame of a window)

Used by the routines at 27951, 28172, 35285, 35627 and 54505.

Input
HL	Repeat count for printing character (e.g. width of window in characters minus 1)

54231

LD A,H

Check whether remaining window's width is zero...

54232

OR L

...and if it is...

54233

RET Z

...then return without doing anything

The operand of the instruction at 54234 represents the index of a character set character to draw. This is modified by the instructions at 27976, 28188, 35031, 35292, 35637 and 54537.

54234

LD A,0

Else, load A with the character index

54236

CALL 54097

Print text/graphic character in A and advance bitmap virtual text cursor

54239

DEC HL

Decrease remaining width

54240

JR 54231

Loop back to 54231