dragon-nx32: add attribute support

Useful as an example hopefully. Everything supported except flash, which isn't
in the hardware in a practical manner.

diff --git a/Kernel/platform-dragon-nx32/devtty.c b/Kernel/platform-dragon-nx32/devtty.c
index 92d0205..e7479e2 100644 (file)
--- a/Kernel/platform-dragon-nx32/devtty.c
+++ b/Kernel/platform-dragon-nx32/devtty.c
@@ -25,6 +25,9 @@ struct s_queue ttyinq[NUM_DEV_TTY + 1] = {    /* ttyinq[0] is never used */
        {tbuf2, tbuf2, tbuf2, TTYSIZ, 0, TTYSIZ / 2}
 };
 
+uint8_t vtattr_cap = VTA_INVERSE|VTA_UNDERLINE|VTA_ITALIC|VTA_BOLD|
+                    VTA_OVERSTRIKE|VTA_NOCURSOR;
+
 /* tty1 is the screen tty2 is the serial port */
 
 /* Output for the system console (kprintf etc) */

diff --git a/Kernel/platform-dragon-nx32/video.s b/Kernel/platform-dragon-nx32/video.s
index 5791a6b..a4b8646 100644 (file)
--- a/Kernel/platform-dragon-nx32/video.s
+++ b/Kernel/platform-dragon-nx32/video.s
@@ -13,6 +13,7 @@
        ; Imports
        ;
        .globl _fontdata_8x8
+       .globl _vidattr
 
        include "kernel.def"
        include "../kernel09.def"
@@ -60,6 +61,74 @@ _plot_char:
        rola
        tfr d,x
        leax _fontdata_8x8,x            ; relative to font
+       ldb _vtattr
+       andb #0x3F              ; drop the bits that don't affect our video
+       beq plot_fast
+
+       ;
+       ;       General purpose plot with attributes, we only fastpath
+       ;       the simple case
+       ;
+       clra
+plot_loop:
+       sta _vtrow
+       ldb _vtattr
+       cmpa #7         ; Underline only applies on the bottom row
+       beq ul_this
+       andb #0xFD
+ul_this:
+       cmpa #3         ; italic shift right for < 3
+       blt ital_1
+       andb #0xFB
+       bra maskdone
+ital_1:
+       cmpa #5         ; italic shift right for >= 5
+       blt maskdone
+       bitb #0x04
+       bne maskdone
+       orb #0x40               ; spare bit borrow for bottom of italic
+       andb #0xFB
+maskdone:
+       lda ,x+                 ; now throw the row away for a bit
+       bitb #0x10
+       bne notbold
+       lsra
+       ora -1,x                ; shift and or to make it bold
+notbold:
+       bitb #0x04              ; italic by shifting top and bottom
+       beq notital1
+       lsra
+notital1:
+       bitb #0x40
+       beq notital2
+       lsla
+notital2:
+       bitb #0x02
+       beq notuline
+       lda #0xff               ; underline by setting bottom row
+notuline:
+       bitb #0x01              ; inverse or not: we are really in inverse
+       bne plot_inv            ; by default so we complement except if
+       coma                    ; inverted
+plot_inv:
+       bitb #0x20              ; overstrike or plot ?
+       bne overstrike
+       sta ,y
+       bra plotnext
+overstrike:
+       anda ,y
+       sta ,y
+plotnext:
+       leay 32,y
+       lda _vtrow
+       inca
+       cmpa #8
+       bne plot_loop
+       puls y,pc
+;
+;      Fast path for normal attributes
+;
+plot_fast:
        lda ,x+                 ; simple 8x8 renderer for now
        coma
        sta 0,y
@@ -246,6 +315,9 @@ _cursor_on:
        stx cursor_save
        ; Fall through
 _cursor_off:
+       ldb _vtattr
+       bitb #0x80
+       bne nocursor
        ldx cursor_save
        com ,x
        com 32,x
@@ -255,8 +327,11 @@ _cursor_off:
        com 160,x
        com 192,x
        com 224,x
+nocursor:
        rts
 
        .area .data
 cursor_save:
        .dw     0
+_vtrow:
+       .db     0
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