| Routines

28660: Update the telephone icon

Used by the routine at 29733. The main entry point is used to make the telephone appear to vibrate as if ringing.
28660 | LD HL,28722 | Point HL at the graphic data for the telephone when ringing (at 28722)
28663 | NOP |
28664 | JR 28669 |
This entry point is also used by the routine at 29733 to make the telephone appear still (as between rings, or when not ringing).
28666 | LD HL,28741 | Point HL at the graphic data for the telephone when not ringing (at 28741)
28669 | LD DE,20654 | Point DE at the display file address of the top pixel row of the top-left tile of the telephone icon
28672 | LD A,6 | Update the top six pixel rows of the top two tiles of the telephone icon
28674 | LDI
28676 | LDI
28678 | DEC E
28679 | DEC E
28680 | INC D
28681 | DEC A
28682 | JR NZ,28674
28684 | LD A,(HL) | Update the bottom two pixel rows of the top-left tile of the telephone icon
28685 | LD (DE),A
28686 | INC L
28687 | INC D
28688 | LD A,(HL)
28689 | LD (DE),A
28690 | LD B,3 | There are three more pixel rows to update
28692 | LD DE,20686 | Point DE at the display file address of the top pixel row of the bottom-left tile of the telephone icon
28695 | INC L | Update the top three pixel rows of the bottom-left tile of the telephone icon
28696 | LD A,(HL)
28697 | LD (DE),A
28698 | INC D
28699 | DJNZ 28695
28701 | RET |