diff --git a/desk.acc/a2d.inc b/desk.acc/a2d.inc
index df9899b..89dde4a 100644
--- a/desk.acc/a2d.inc
+++ b/desk.acc/a2d.inc
@@ -58,7 +58,8 @@ A2D_QUERY_SCREEN        := $03  ; Get screen state
         ;; .byte 0,0,0,0        ???
         ;; .byte hthick         horizontal pen thickness
         ;; .byte vthick         vertical pen thickness
-        ;; .byte 0,$7F          ???
+        ;; .byte 0              ??? fill mode?
+        ;; .byte tmsk           AND mask for text, default $7F
         ;; .addr font           A2D_DEFAULT_FONT
 
 A2D_SET_STATE   := $04          ; Set full drawing state
@@ -77,7 +78,8 @@ A2D_SET_STATE   := $04          ; Set full drawing state
         ;; .byte 0,0,0,0        ???
         ;; .byte hthick         horizontal pen thickness
         ;; .byte vthick         vertical pen thickness
-        ;; .byte 0, $7F
+        ;; .byte 0              ??? fill mode?
+        ;; .byte tmsk           AND mask for text, default $7F
         ;; .addr font           A2D_DEFAULT_FONT
 
         ;; $05 used in DeskTop but not DAs - icon click
@@ -255,7 +257,8 @@ A2D_CREATE_WINDOW := $38
         ;; .byte 0,0,0,0        ???
         ;; .byte hthick
         ;; .byte vthick
-        ;; .byte $00,$7F        ???
+        ;; .byte 0              ??? fill mode?
+        ;; .byte tmsk           AND mask for text, default $7F
         ;; .addr font           A2D_DEFAULT_FONT
         ;; .byte 0,0            ???
 
@@ -501,9 +504,8 @@ end:
 
         A2D_DEFAULT_FONT := $8800
 
-        font_unk        := $8800 ; = $00
-        font_size_count := $8801 ; = $7F
-                                 ; num glyphs + 1 (for height) / max glyphs ?
+        font_unk        := $8800 ; = $00 - ???
+        font_size_count := $8801 ; = $7F - max glyph number
                                  ; looks like an address ($7F00) but is used as count
         font_height     := $8802 ; 9 pixels
         font_width_table := $8803 ; width in pixels, indexed by ASCII code
diff --git a/desk.acc/calc_fixed.s b/desk.acc/calc_fixed.s
index f8b5201..065c9bf 100644
--- a/desk.acc/calc_fixed.s
+++ b/desk.acc/calc_fixed.s
@@ -688,7 +688,8 @@ mskor:  .byte   0
         .byte   0,0,0,0         ; ???
 hthick: .byte   0
 vthick: .byte   0
-        .byte   0,0             ; ???
+        .byte   0               ; ???
+tmask:  .byte   0
 font:   .addr   0
         .byte   0,0             ; ???
 .endproc
@@ -740,7 +741,7 @@ w2:     .word   window_width
 h2:     .word   window_height
 left:   .word   default_left
 top:    .word   default_top
-saddr:  .word   A2D_SCREEN_ADDR
+saddr:  .addr   A2D_SCREEN_ADDR
 stride: .word   A2D_SCREEN_STRIDE
 hoffset:.word   0
 voffset:.word   0
@@ -752,9 +753,10 @@ mskor:  .byte   A2D_DEFAULT_MSKOR
         .byte   0,0,0,0         ; ???
 hthick: .byte   1
 vthick: .byte   1
-        .byte   $00,$7F         ; ???
+        .byte   0               ; ???
+tmask:  .byte   0
 font:   .addr   A2D_DEFAULT_FONT
-        .byte   $00,$00         ; ???
+        .byte   0,0             ; ???
 .endproc
 create_window_params_top := create_window_params::top
 
diff --git a/desk.acc/calculator.s b/desk.acc/calculator.s
index badb21d..21c1f32 100644
--- a/desk.acc/calculator.s
+++ b/desk.acc/calculator.s
@@ -693,7 +693,8 @@ mskor:  .byte   0
         .byte   0,0,0,0         ; ???
 hthick: .byte   0
 vthick: .byte   0
-        .byte   0,0             ; ???
+        .byte   0               ; ???
+tmask:  .byte   0
 font:   .addr   0
 .endproc
         .assert * - state_params = 36, error
@@ -747,7 +748,7 @@ w2:     .word   window_width
 h2:     .word   window_height
 left:   .word   default_left
 top:    .word   default_top
-saddr:  .word   A2D_SCREEN_ADDR
+saddr:  .addr   A2D_SCREEN_ADDR
 stride: .word   A2D_SCREEN_STRIDE
 hoffset:.word   0
 voffset:.word   0
@@ -759,7 +760,8 @@ mskor:  .byte   A2D_DEFAULT_MSKOR
         .byte   0,0,0,0         ; ???
 hthick: .byte   1
 vthick: .byte   1
-        .byte   $00,$7F         ; ???
+        .byte   0               ; ???
+tmask:  .byte   $7f
 font:   .addr   A2D_DEFAULT_FONT
         .byte   0,0             ; ???
 .endproc
diff --git a/desk.acc/date.s b/desk.acc/date.s
index 3baf040..1562a64 100644
--- a/desk.acc/date.s
+++ b/desk.acc/date.s
@@ -272,8 +272,8 @@ left:   .word   180
 top:    .word   50
 saddr:  .addr   A2D_SCREEN_ADDR
 stride: .word   A2D_SCREEN_STRIDE
-hoff:   .word   0
-voff:   .word   0
+hoffset:.word   0
+voffset:.word   0
 width:  .word   $C7
 height: .word   $40
 .endproc
@@ -283,7 +283,8 @@ mskor:  .byte   A2D_DEFAULT_MSKOR
         .byte   0,0,0,0         ; ???
 hthick: .byte   4
 vthick: .byte   2
-        .byte   $00,$7F         ; ???
+        .byte   0               ; ???
+tmask:  .byte   $7F
 font:   .addr   A2D_DEFAULT_FONT
         .byte   0,0             ; ???
 .endproc
diff --git a/desk.acc/puzzle.s b/desk.acc/puzzle.s
index 86a75f6..f429c9c 100644
--- a/desk.acc/puzzle.s
+++ b/desk.acc/puzzle.s
@@ -616,7 +616,8 @@ mskor:  .byte   A2D_DEFAULT_MSKOR
         .byte   0,0,0,0         ; ???
 hthick: .byte   1
 vthick: .byte   1
-        .byte   $00,$7F         ; ???
+        .byte   0               ; ???
+tmask:  .byte   $7F
 font:   .addr   A2D_DEFAULT_FONT
         .byte   0,0             ; ???
 .endproc
@@ -637,7 +638,8 @@ mskor:  .byte   A2D_DEFAULT_MSKOR
         .byte   0,0,0,0         ; ???
 hthick: .byte   1
 vthick: .byte   1
-        .byte   $00,$7F         ; ???
+        .byte   0               ; ???
+tmask:  .byte   $7F
 font:   .addr   A2D_DEFAULT_FONT
         .byte   0,0             ; ???
 .endproc
diff --git a/desk.acc/show_image_file.s b/desk.acc/show_image_file.s
index e30d83e..2b312f6 100644
--- a/desk.acc/show_image_file.s
+++ b/desk.acc/show_image_file.s
@@ -209,7 +209,7 @@ h2:     .word   default_height
 .proc box
 left:   .word   default_left
 top:    .word   default_top
-addr:   .word   A2D_SCREEN_ADDR
+saddr:  .addr   A2D_SCREEN_ADDR
 stride: .word   A2D_SCREEN_STRIDE
 hoffset:.word   0
 voffset:.word   0
@@ -223,7 +223,8 @@ mskor:  .byte   A2D_DEFAULT_MSKOR
         .byte   0,0,0,0         ; ???
 hthick: .byte   1
 vthick: .byte   1
-        .byte   $00,$7F         ; ???
+        .byte   0               ; ???
+tmask:  .byte   $7F
 font:   .addr   A2D_DEFAULT_FONT
         .byte   0,0             ; ???
 .endproc
diff --git a/desk.acc/show_text_file.s b/desk.acc/show_text_file.s
index a6e376d..05a5423 100644
--- a/desk.acc/show_text_file.s
+++ b/desk.acc/show_text_file.s
@@ -318,7 +318,7 @@ h2:     .word   default_height
 .proc box
 left:   .word   default_left
 top:    .word   default_top
-addr:   .word   A2D_SCREEN_ADDR
+saddr:  .addr   A2D_SCREEN_ADDR
 stride: .word   A2D_SCREEN_STRIDE
 hoffset:.word   0               ; Also used for A2D_FILL_RECT
 voffset:.word   0
@@ -329,12 +329,13 @@ height: .word   default_height
 pattern:.res    8, $00
 mskand: .byte   A2D_DEFAULT_MSKAND
 mskor:  .byte   A2D_DEFAULT_MSKOR
-        .byte   $00,$00,$00,$00
+        .byte   0,0,0,0         ; ???
 hthick: .byte   1
 vthick: .byte   1
-        .byte   $00,$7F
+        .byte   0               ; ???
+tmask:  .byte   $7F
 font:   .addr   A2D_DEFAULT_FONT
-        .byte   0,0
+        .byte   0,0             ; ???
 .endproc
 
         ;; gets copied over window_params::box after mode is drawn