84PCSE:BCALLs:4D6E

Synopsis

Hypothesized Official Name: EraseRectBorder

BCALL Address: 4D6Eh

Draw a white rectangular outline 1 pixel wide.

Inputs

• HL = X coordinate of left edge
• DE = X coordinate of right edge (must be greater than HL and at most 319)
• B = Y coordinate of top edge (from top of screen)
• C = Y coordinate of bottom edge (must be greater than B and at most 239)

Outputs

• (penFGColor) = 0FFFFh

Destroys

• AF
• Interrupts disabled

Comments

The rectangle is drawn only to the LCD, never to the graph buffer.

The dimensions of the enclosed area are (HL-DE-1) × (C-B-1). The outer dimensions of the border are (HL-DE+1) × (C-B+1).