added size optimized monochrom soft80 driver

libsrc/c64/soft80mono_color.s

@@ -0,0 +1,65 @@
+;
+; Groepaz/Hitmen, 19.10.2015
+;
+; high level implementation for the monochrome soft80 implementation
+;
+; unsigned char __fastcall__ textcolor (unsigned char color);
+; unsigned char __fastcall__ bgcolor (unsigned char color);
+;
+
+        .export         soft80mono_textcolor, soft80mono_bgcolor
+        .import         soft80mono_internal_cellcolor, soft80mono_internal_bgcolor
+
+        .importzp       tmp1
+
+        .include        "c64.inc"
+        .include        "soft80.inc"
+
+soft80mono_textcolor:
+        ldx     CHARCOLOR                       ; get old value
+        stx     tmp1                            ; save old value
+        sta     CHARCOLOR                       ; set new value
+
+mkcharcolor:
+        lda     soft80mono_internal_bgcolor
+        asl     a
+        asl     a
+        asl     a
+        asl     a
+        ora     CHARCOLOR
+        sta     soft80mono_internal_cellcolor   ; text/bg combo for new chars
+
+        sei
+        ldy     $01
+        lda     #$34                            ; enable RAM under I/O
+        sta     $01
+
+        lda     soft80mono_internal_cellcolor
+        ; clear loop for vram
+        ldx     #$00
+@lp1:
+        sta     soft80_vram,x
+        sta     soft80_vram+$100,x
+        sta     soft80_vram+$200,x
+        sta     soft80_vram+$2e8,x
+        inx
+        bne     @lp1
+
+        sty     $01
+        cli
+
+        lda     tmp1                            ; get old value
+        rts
+
+soft80mono_bgcolor:
+        ldx     soft80mono_internal_bgcolor     ; get old value
+        stx     tmp1                            ; save old value
+        sta     soft80mono_internal_bgcolor     ; set new value
+
+        jmp     mkcharcolor
+
+;-------------------------------------------------------------------------------
+; force the init constructor to be imported
+
+        .import soft80mono_init
+conio_init      = soft80mono_init