started work on VIC-IV cursor

src/aliases/,aliases_cpu.s

@@ -338,6 +338,15 @@
 
 // Flat memory access support
 
+.pseudocommand lda_lp arg {
+	.var value = arg.getValue()
+	.var type  = arg.getType()
+	.if(type != AT_IZEROPAGEZ) .error "'lda_lp' only accepts AT_IZEROPAGEZ"
+	.if(value > $FF )          .error "'lda_lp' requires zeropage address"
+	nop
+	.byte $B2, value
+}
+
 .pseudocommand sta_lp arg {
 	.var value = arg.getValue()
 	.var type  = arg.getType()

src/kernal/board_m65/mega65_imports.s

@@ -34,6 +34,8 @@
 .label wait_x_bars                     = KERNAL_0.wait_x_bars
 .label viciv_unhide                    = KERNAL_0.viciv_unhide
 
+.label m65_scrtab_rowoffset_lo         = KERNAL_0.m65_scrtab_rowoffset_lo
+.label m65_scrtab_rowoffset_hi         = KERNAL_0.m65_scrtab_rowoffset_hi
 .label m65_scrtab_txtwidth             = KERNAL_0.m65_scrtab_txtwidth
 .label m65_scrtab_txtheight            = KERNAL_0.m65_scrtab_txtheight
 

src/kernal/interrupts/ea31.default_irq_handler.s

@@ -18,7 +18,7 @@ default_irq_handler:
 #if ROM_LAYOUT_M65
 
 	jsr M65_ISMODE65
-	bne !+
+	bcs !+
 
 	jsr m65_cursor_blink
 

src/kernal/screen/cursor.s

@@ -17,6 +17,7 @@
 
 
 cursor_blink:
+
 	// Is the cursor enabled?
 	lda BLNSW
 	bne cursor_blink_end
@@ -50,26 +51,31 @@ cursor_draw:
 	bne cursor_blink_timer_reset // branches always
 
 cursor_disable:
+
 	lda #$80
 	sta BLNSW
 
 	// FALLTHROUGH
 
 cursor_hide_if_visible:
+
 	lda BLNON
 	beq cursor_blink_end
 
+	// FALLTROUGH
+
 cursor_undraw:
 
+	// Prevent interrupts from updating cursor
+	lda #0
+	sta BLNON
+
 	jsr screen_get_clipped_PNTR
 	lda GDBLN
 	sta (PNT),y
 	lda GDCOL
 	sta (USER),y
 	
-	lda #0
-	sta BLNON
-
 	// FALLTROUGH
 
 cursor_blink_timer_reset:

src/kernal/screen_m65/mega65_chrout_screen.s

@@ -8,7 +8,9 @@
 
 m65_chrout_screen:
 
-	// XXX hide cursor if visible
+	jsr m65_cursor_hide_if_visible
+
+	// Retrieve the character to output
 
 	lda SCHAR
 	tax
@@ -127,6 +129,7 @@ m65_chrout_fix_column_row_win:
 
 m65_chrout_screen_done:
 
-	// XXX reenable cursor
+	jsr m65_cursor_show_if_enabled
 
+	// XXX change this to return success
 	rts

src/kernal/screen_m65/mega65_cursor.s

@@ -1,9 +1,37 @@
-// #LAYOUT# M65 KERNAL_0 #TAKE
+// #LAYOUT# M65 KERNAL_1 #TAKE
 // #LAYOUT# *   *        #IGNORE
 
+//
+// Variables used:
+// - BLNSW (cursor blink switch)
+// - BLNCT (cursor blink countdown)
+// - GDBLN (cursor saved character)
+// - BLNON (if cursor is visible)
+// - GDCOL (colour under cursor)
+//
 
-m65_cursor_blink:
+m65_cursor_hide_if_visible:
+
+	lda BLNON
+	beq m65_cursor_end
+
+	// FALLTROUGH
+
+m65_cursor_undraw:
 
 	// XXX provide implementation
 
 	rts
+
+
+m65_cursor_show_if_enabled:
+
+	// XXX provide implementation
+
+	nop
+
+	// FALLTROUGH
+
+m65_cursor_end:
+
+	rts

src/kernal/screen_m65/mega65_cursor_blink.s

@@ -0,0 +1,93 @@
+// #LAYOUT# M65 KERNAL_0 #TAKE
+// #LAYOUT# *   *        #IGNORE
+
+//
+// Variables used:
+// - BLNSW (cursor blink switch)
+// - BLNCT (cursor blink countdown)
+// - GDBLN (cursor saved character)
+// - BLNON (if cursor is visible)
+// - GDCOL (colour under cursor)
+//
+
+
+m65_cursor_blink:
+
+	// Preserve .Z
+	phz
+
+	// Is the cursor enabled?
+	lda BLNSW
+	bne m65_cursor_blink_end
+
+	// Do we need to redraw things?
+	dec BLNCT
+	bpl m65_cursor_blink_end
+
+	// Prepare .Z and long pointer to screen position
+	ldz M65__TXTCOL
+	lda M65_SCRVIEW+0
+	sta M65_LPNT_IRQ+0
+	lda M65_SCRVIEW+1
+	sta M65_LPNT_IRQ+1
+	lda M65_SCRSEG+0
+	sta M65_LPNT_IRQ+2
+	lda M65_SCRSEG+1
+	sta M65_LPNT_IRQ+3
+
+	// Add row offset to the long pointer
+	ldy M65__TXTROW
+	clc
+	lda m65_scrtab_rowoffset_lo,y
+	adc M65_LPNT_IRQ+0
+	sta M65_LPNT_IRQ+0
+	lda m65_scrtab_rowoffset_hi,y
+	adc M65_LPNT_IRQ+1
+	sta M65_LPNT_IRQ+1	
+
+	// Check if cursor was visible or not, and toggle
+	lda BLNON
+	bne m65_cursor_blink_undraw
+
+	// FALLTROUGH
+
+m65_cursor_blink_draw:
+
+	lda #1
+	sta BLNON
+
+	// Cursor draw - character
+	lda_lp (M65_LPNT_IRQ),z
+	sta GDBLN
+	eor #$80
+	sta_lp (M65_LPNT_IRQ),z
+
+	// Cursor draw - color
+	// XXX provide implementation
+
+m65_cursor_blink_timer_reset:
+
+	// Rest blink counter (Mapping the 64, p39-40)
+	lda #20
+	sta BLNCT
+
+	// FALLTROUGH
+
+m65_cursor_blink_end:
+
+	plz
+	rts
+
+m65_cursor_blink_undraw:
+
+	lda #0
+	sta BLNON
+
+	// Cursor undraw - character
+	lda GDBLN
+	sta_lp (M65_LPNT_IRQ),z
+
+	// Cursor undraw - color
+	// XXX provide implementation
+
+	jmp_8 m65_cursor_blink_timer_reset

src/kernal/screen_m65/mega65_screen_table_roff_hi.s

@@ -0,0 +1,13 @@
+// #LAYOUT# M65 KERNAL_0 #TAKE
+// #LAYOUT# *   *        #IGNORE
+
+
+// XXX consider moving this back to extended memory, and just store the offset in RAM
+
+m65_scrtab_rowoffset_hi:     // row offsets - high bytes
+
+	.byte >(80 *  0), >(80 *  1), >(80 *  2), >(80 *  3), >(80 *  4), >(80 *  5), >(80 *  6), >(80 *  7), >(80 *  8), >(80 *  9)
+	.byte >(80 * 10), >(80 * 11), >(80 * 12), >(80 * 13), >(80 * 14), >(80 * 15), >(80 * 16), >(80 * 17), >(80 * 18), >(80 * 19)
+	.byte >(80 * 20), >(80 * 21), >(80 * 22), >(80 * 23), >(80 * 24), >(80 * 25), >(80 * 26), >(80 * 27), >(80 * 28), >(80 * 29)
+	.byte >(80 * 30), >(80 * 31), >(80 * 32), >(80 * 33), >(80 * 34), >(80 * 35), >(80 * 36), >(80 * 37), >(80 * 38), >(80 * 39)
+	.byte >(80 * 40), >(80 * 41), >(80 * 42), >(80 * 43), >(80 * 44), >(80 * 45), >(80 * 46), >(80 * 47), >(80 * 48), >(80 * 49)

src/kernal/screen_m65/mega65_screen_table_roff_lo.s

@@ -0,0 +1,13 @@
+// #LAYOUT# M65 KERNAL_0 #TAKE
+// #LAYOUT# *   *        #IGNORE
+
+
+// XXX consider moving this back to extended memory, and just store the offset in RAM
+
+m65_scrtab_rowoffset_lo:     // row offsets - low bytes
+
+	.byte <(80 *  0), <(80 *  1), <(80 *  2), <(80 *  3), <(80 *  4), <(80 *  5), <(80 *  6), <(80 *  7), <(80 *  8), <(80 *  9)
+	.byte <(80 * 10), <(80 * 11), <(80 * 12), <(80 * 13), <(80 * 14), <(80 * 15), <(80 * 16), <(80 * 17), <(80 * 18), <(80 * 19)
+	.byte <(80 * 20), <(80 * 21), <(80 * 22), <(80 * 23), <(80 * 24), <(80 * 25), <(80 * 26), <(80 * 27), <(80 * 28), <(80 * 29)
+	.byte <(80 * 30), <(80 * 31), <(80 * 32), <(80 * 33), <(80 * 34), <(80 * 35), <(80 * 36), <(80 * 37), <(80 * 38), <(80 * 39)
+	.byte <(80 * 40), <(80 * 41), <(80 * 42), <(80 * 43), <(80 * 44), <(80 * 45), <(80 * 46), <(80 * 47), <(80 * 48), <(80 * 49)

src/kernal/screen_m65/mega65_screen_tables_misc.s

@@ -26,22 +26,6 @@ m65_scrtab_scrolx:           // values for VIC_SCROLX
 	.byte $CA
 	.byte $CA
 
-m65_scrtab_rowoffset_lo:     // row offsets - low bytes
-
-	.byte <(80 *  0), <(80 *  1), <(80 *  2), <(80 *  3), <(80 *  4), <(80 *  5), <(80 *  6), <(80 *  7), <(80 *  8), <(80 *  9)
-	.byte <(80 * 10), <(80 * 11), <(80 * 12), <(80 * 13), <(80 * 14), <(80 * 15), <(80 * 16), <(80 * 17), <(80 * 18), <(80 * 19)
-	.byte <(80 * 20), <(80 * 21), <(80 * 22), <(80 * 23), <(80 * 24), <(80 * 25), <(80 * 26), <(80 * 27), <(80 * 28), <(80 * 29)
-	.byte <(80 * 30), <(80 * 31), <(80 * 32), <(80 * 33), <(80 * 34), <(80 * 35), <(80 * 36), <(80 * 37), <(80 * 38), <(80 * 39)
-	.byte <(80 * 40), <(80 * 41), <(80 * 42), <(80 * 43), <(80 * 44), <(80 * 45), <(80 * 46), <(80 * 47), <(80 * 48), <(80 * 49)
-
-m65_scrtab_rowoffset_hi:     // row offsets - high bytes
-
-	.byte >(80 *  0), >(80 *  1), >(80 *  2), >(80 *  3), >(80 *  4), >(80 *  5), >(80 *  6), >(80 *  7), >(80 *  8), >(80 *  9)
-	.byte >(80 * 10), >(80 * 11), >(80 * 12), >(80 * 13), >(80 * 14), >(80 * 15), >(80 * 16), >(80 * 17), >(80 * 18), >(80 * 19)
-	.byte >(80 * 20), >(80 * 21), >(80 * 22), >(80 * 23), >(80 * 24), >(80 * 25), >(80 * 26), >(80 * 27), >(80 * 28), >(80 * 29)
-	.byte >(80 * 30), >(80 * 31), >(80 * 32), >(80 * 33), >(80 * 34), >(80 * 35), >(80 * 36), >(80 * 37), >(80 * 38), >(80 * 39)
-	.byte >(80 * 40), >(80 * 41), >(80 * 42), >(80 * 43), >(80 * 44), >(80 * 45), >(80 * 46), >(80 * 47), >(80 * 48), >(80 * 49)
-
 // Jumptable for screen control codes support. To improve performance, should be sorted
 // starting from the least probable routine.