; draw_box.asm -- one-shot static VRAM injection, then return.
;
; Draws three 32x32 solid-white boxes at framebuffer (x,y):
;   A (50,50)   -- root weave, outside every window
;   B (250,400) -- inside the Terminal Manager window body (white area)
;   C (930,750) -- root weave, lower right
; Writes marker words and returns with `rets`, so the rdebug session survives.
;
; Framebuffer model (harness/mame/RENDER_REPORT.md): base bit 04000000h,
; 1024 bits per row, bit 0 = leftmost pixel, LSB-first in each 16-bit word.
;
; Linked at bit 01840000h by dwt/visual/build.sh.

	.text
_start:
	setf	16, 0, 0
	setf	32, 0, 1
	movi	0FFFFh, a0, L		; pattern

	; ---- box A: (50,50), 32 rows x 2 words = 32x32 px -------------
	movi	0400C832h, a2, L	; 04000000h + 50*1024 + 50
	movi	32, a3, L
	movi	2, a4, L
rowA:
	move	a4, a5
wordA:
	move	a0, *a2+, 0
	dsjs	a5, wordA
	addi	03E0h, a2		; 1024 - 32 bits
	dsjs	a3, rowA

	; ---- box B: (250,400) ----------------------------------------
	movi	040640FAh, a2, L	; 04000000h + 400*1024 + 250
	movi	32, a3, L
	movi	2, a4, L
rowB:
	move	a4, a5
wordB:
	move	a0, *a2+, 0
	dsjs	a5, wordB
	addi	03E0h, a2
	dsjs	a3, rowB

	; ---- box C: (930,750) ----------------------------------------
	movi	040BBBA2h, a2, L	; 04000000h + 750*1024 + 930
	movi	32, a3, L
	movi	2, a4, L
rowC:
	move	a4, a5
wordC:
	move	a0, *a2+, 0
	dsjs	a5, wordC
	addi	03E0h, a2
	dsjs	a3, rowC

	movi	0D2A0h, a0, L
	move	a0, @01850020h, 0	; DRAW_MARK = D2A0
	movi	0B0C0h, a0, L
	move	a0, @01850030h, 0	; DRAW_MARK2 = B0C0
	rets
	.end