vdp1: Allow mixed VDP/non VDP

We add a .equ which indicates whether the vdp1 driver should provide the
functions for vt.c or ones that can be wrapped. For MSX we are happy as we
are but for MTX512 we can support a VDP and a 6845 at the same time.

diff --git a/Kernel/dev/vdp1.s b/Kernel/dev/vdp1.s
index 8d2b464..9e79c67 100644 (file)
--- a/Kernel/dev/vdp1.s
+++ b/Kernel/dev/vdp1.s
@@ -1,14 +1,14 @@
             .module vdp
 
            ; video driver
-           .globl _scroll_up
-           .globl _scroll_down
-           .globl _plot_char
-           .globl _clear_lines
-           .globl _clear_across
-           .globl _cursor_on
-           .globl _cursor_off
-           .globl _cursorpos
+           .globl scroll_up
+           .globl scroll_down
+           .globl plot_char
+           .globl clear_lines
+           .globl clear_across
+           .globl cursor_on
+           .globl cursor_off
+           .globl cursorpos
 
            .globl _vdpport
 
@@ -46,7 +46,7 @@ vdpout:           ld bc, (_vdpport)
 ;
 
 
-_videopos:     ; turn E=Y D=X into HL = addr
+videopos:      ; turn E=Y D=X into HL = addr
                ; pass B = 0x40 if writing
                ; preserves C
            ld a, e                     ; 0-24 Y
@@ -68,7 +68,10 @@ _videopos:   ; turn E=Y D=X into HL = addr
 ;
 ;      Eww.. wonder if VT should provide a hint that its the 'next char'
 ;
-_plot_char: pop hl
+               .if VDP_DIRECT
+_plot_char:
+               .endif
+plot_char:  pop hl
            pop de                      ; D = x E = y
            pop bc
            push bc
@@ -76,7 +79,7 @@ _plot_char: pop hl
            push hl
 plotit:
            ld b, #0x40                 ; writing
-           call _videopos
+           call videopos
            ld a, c
 plotit2:
            ld bc, (_vdpport)
@@ -101,7 +104,10 @@ scrollbuf:   .ds           40
 ;
 ;      We don't yet use attributes...
 ;
+               .if VDP_DIRECT
 _scroll_down:
+               .endif
+scroll_down:
            ret
            ld b, #23
            ld de, #0x3C0       ; start of bottom line
@@ -129,7 +135,10 @@ upline:
            djnz upline
            ret
 
+               .if VDP_DIRECT
 _scroll_up:
+               .endif
+scroll_up:
            ret
            ld b, #23
            ld de, #40          ; start of second line
@@ -157,7 +166,10 @@ downline:   push bc
            djnz downline
            ret
 
+               .if VDP_DIRECT
 _clear_lines:
+               .endif
+clear_lines:
            pop hl
            pop de      ; E = line, D = count
            push de
@@ -165,7 +177,7 @@ _clear_lines:
            ld c, d
            ld d, #0
            ld b, #0x40
-           call _videopos
+           call videopos
            ld e, c
            ld bc, (_vdpport)
            out (c), l
@@ -183,7 +195,10 @@ l1:            out (c), a          ; Inner loop clears a line, outer counts
            jr nz, l2
            ret
 
+               .if VDP_DIRECT
 _clear_across:
+               .endif
+clear_across:
            pop hl
            pop de      ; DE = coords
            pop bc      ; C = count
@@ -191,7 +206,7 @@ _clear_across:
            push de
            push hl
            ld b, #0x40
-           call _videopos
+           call videopos
            ld a, c
            ld bc, (_vdpport)
            out (c), l
@@ -206,14 +221,17 @@ l3:           out (c), a
 ;
 ;      FIXME: should use attribute blink flag not a char
 ;
+               .if VDP_DIRECT
 _cursor_on:
+               .endif
+cursor_on:
            pop hl
            pop de
            push de
            push hl
            ld (cursorpos), de
            ld b, #0x00                 ; reading
-           call _videopos
+           call videopos
            ld a, c
            ld bc, (_vdpport)
            out (c), l                  ; address
@@ -225,7 +243,10 @@ _cursor_on:
            ld a, #'_'                  ; write the cursor
            jp plotit2
 
+               .if VDP_DIRECT
 _cursor_off:
+               .endif
+cursor_off:
            ld de, (cursorpos)
            ld a, (cursorpeek)
            ld c, a

diff --git a/Kernel/platform-msx1/vdp.s b/Kernel/platform-msx1/vdp.s
index a35d941..48d492b 100644 (file)
--- a/Kernel/platform-msx1/vdp.s
+++ b/Kernel/platform-msx1/vdp.s
@@ -3,11 +3,24 @@
             .include "kernel.def"
             .include "../kernel.def"
 
-           .include "../dev/vdp1.s"
 
 
            .area _COMMONMEM
 
+           .globl _cursor_on
+           .globl _cursor_off
+           .globl _clear_across
+           .globl _clear_lines
+           .globl _scroll_up
+           .globl _scroll_down
+           .globl _plot_char
+
+;
+; VDP routines are directly hooked into the vt layer
+;
+VDP_DIRECT     .equ    1
+
+           .include "../dev/vdp1.s"
 ;
 ;      FIXME: should use vdpport, but right now vdpport is in data not
 ;      common space.