added some more comments and -headers

libsrc/c64/extra/soft80.s

@@ -1,3 +1,7 @@
+;
+; Groepaz/Hitmen, 12.10.2015
+;
+; import/overload stubs for the soft80 implementation
 
 
         ; soft80_cgetc.s

libsrc/c64/soft80.inc

@@ -1,3 +1,7 @@
+;
+; Groepaz/Hitmen, 12.10.2015
+;
+; internal constants for the soft80 implementation
 
 soft80_lo_charset       = $d000
 soft80_hi_charset       = $d400
@@ -8,6 +12,7 @@ soft80_bitmap           = $e000
 charsperline            = 80
 screenrows              = 25
 
+; FIXME: these should match petscii and perhaps come from a common cbm.inc?
 CH_ESC                  = 95
 CH_HLINE                = 96
 CH_CROSS                = 123

libsrc/c64/soft80_charset.s

@@ -1,5 +1,5 @@
 ;
-; Groepaz/Hitmen, 10.10.2015
+; Groepaz/Hitmen, 12.10.2015
 ;
 ; character set for use with the soft80 implementation
 ;
@@ -14,6 +14,8 @@
 ;   - $60 - $7f screencodes $40 - $5f (petscii codes $60 - $7f)
 ; - only 128 characters are defined here, the soft80 implementation will invert
 ;   the graphics data for inverted display on the fly.
+; - since the charset is 4 by 8 pixels, only the lower 4bit of each byte is
+;   used. the upper bits have to be 0.
 ; - finally the lower 4bits are "inverted", ie a space character is represented
 ;   as $0f, $0f, $0f, $0f, $0f, $0f, $0f, $0f
 ;
@@ -29,6 +31,15 @@
 ; +280 ....xxxx ......xx ........ ....xxxx
 ; +300 ....xxxx ......xx ........ ....xxxx
 ; +380 ....xxxx ......xx ........ ....xxxx
+; [...]
+; +040 ....x.xx ....xxxx ....xxxx ....xxxx
+; +0c0 .....x.x ....xxxx .....xxx ....xxxx
+; +140 .......x ....x.xx .....xxx ....x..x
+; +1c0 .......x ....xx.x ......xx .....xxx
+; +240 .....xxx ....x..x .....x.x .....xxx
+; +2c0 .....x.x .....x.x .....x.x .....xxx
+; +340 ....x.xx ....x..x ......xx ....x..x
+; +3c0 ....xxxx ....xxxx ....xxxx ....xxxx
 
         .export         soft80_charset
 

libsrc/c64/soft80_chline.s

@@ -1,4 +1,6 @@
 ;
+; Groepaz/Hitmen, 12.10.2015
+;
 ; void chlinexy (unsigned char x, unsigned char y, unsigned char length);
 ; void chline (unsigned char length);
 ;

libsrc/c64/soft80_color.s

@@ -1,4 +1,6 @@
 ;
+; Groepaz/Hitmen, 12.10.2015
+;
 ; unsigned char __fastcall__ textcolor (unsigned char color);
 ; unsigned char __fastcall__ bgcolor (unsigned char color);
 ; unsigned char __fastcall__ bordercolor (unsigned char color);

libsrc/c64/soft80_conio.s

@@ -25,7 +25,8 @@ soft80_init:
         lda     #$c8
         sta     VIC_CTRL2
 
-; copy charset to RAM under I/O -> FIXME: generate at runtime
+        ; copy charset to RAM under I/O
+        ; FIXME: move charset and this constructor into init segment
         sei
         lda     $01
         pha

libsrc/c64/soft80_cvline.s

@@ -1,4 +1,6 @@
 ;
+; Groepaz/Hitmen, 12.10.2015
+;
 ; void cvlinexy (unsigned char x, unsigned char y, unsigned char length);
 ; void cvline (unsigned char length);
 ;

libsrc/c64/soft80_kclrscr.s

@@ -1,3 +1,8 @@
+;
+; Groepaz/Hitmen, 12.10.2015
+;
+; lowlevel kclrscr for soft80 implementation
+;
 
         .export         soft80_kclrscr
         .import         soft80_kplot

libsrc/c64/soft80_kplot.s

@@ -1,4 +1,10 @@
 
+;
+; Groepaz/Hitmen, 12.10.2015
+;
+; lowlevel kplot function for the soft80 implementation
+;
+
         .export         soft80_kplot
 
         .include        "c64.inc"
@@ -35,6 +41,9 @@ soft80_kplot:
         ldy     CURS_X
         rts
 
+        ; FIXME: the following tables take up 260 bytes, perhaps move them
+        ;        to 0xdc00... area in ram under i/o
+
         .rodata
 _bitmapxlo:
         .repeat 80,col

libsrc/c64/soft80_scrsize.s

@@ -1,3 +1,8 @@
+;
+; Groepaz/Hitmen, 12.10.2015
+;
+; lowlevel screensize function for the soft80 implementation
+;
 
         .export         soft80_screensize