ti84: use Grid subsystem

Also, rename CLRLN to NEWLN and make it clear that it's only called
on entering a new line. This way, we can set Z offset in there for
the TI-84+ LCD driver.

arch/z80/ti84/blk/605

@@ -1,6 +1,7 @@
 ( Required config: LCD_MEM )
 : _mem+ [ LCD_MEM LITN ] @ + ;
 : FNTW 3 ; : FNTH 5 ;
+: COLS 96 FNTW 1+ / ; : LINES 64 FNTH 1+ / ;
 ( Wait until the lcd is ready to receive a command. It's a bit
   weird to implement a waiting routine in asm, but the forth
   version is a bit heavy and we don't want to wait longer than

arch/z80/ti84/blk/606

@@ -1,11 +1,7 @@
-( Current Y position on the LCD, that is, where we're going to
-  spit our next glyph. )
-: LCD_CURY 0 _mem+ ;
-: LCD_CURX 1 _mem+ ;
 ( two pixel buffers that are 8 pixels wide (1b) by FNTH
   pixels high. This is where we compose our resulting pixels
   blocks when spitting a glyph. )
-: LCD_BUF 2 _mem+ ;
+: LCD_BUF 0 _mem+ ;
 : _cmd 0x10 ( CMD ) PC! _wait ;
 : _data! 0x11 ( DATA ) PC! _wait ;
 : _data@ 0x11 ( DATA ) PC@ _wait ;

arch/z80/ti84/blk/607

@@ -3,7 +3,7 @@
 : _col! ( col -- ) 0x20 + _cmd ;
 : _row! ( row -- ) 0x80 + _cmd ;
 : LCD$
-    H@ [ LCD_MEM LITN ] ! FNTH 2 * 2+ ALLOT
+    H@ [ LCD_MEM LITN ] ! FNTH 2 * ALLOT
     LCDON 0x01 ( 8-bit mode ) _cmd
     FNTH 1+ _zoff!
 ;

arch/z80/ti84/blk/608

@@ -5,10 +5,7 @@
         11 0 DO 0 _data! LOOP
         _xinc 0 _data!
     LOOP ;
-: _clrln ( n ) FNTH 1+ _clrrows ;
+: NEWLN ( ln -- )
+    DUP 1+ FNTH 1+ * _zoff!
+    FNTH 1+ * FNTH 1+ _clrrows ;
 : LCDCLR 0 64 _clrrows ;
-( Changes the current line and go back to leftmost column )
-: _lf
-    LCD_CURY C@ FNTH 1+ + DUP 63 > IF DROP 0 THEN
-    DUP _clrln DUP FNTH 1+ + _zoff!
-    LCD_CURY C! 0 LCD_CURX C! ;

arch/z80/ti84/blk/609

@@ -1,15 +1,16 @@
-: _glyph> ( a -- )
-    LCD_CURY C@ _row! LCD_CURX C@ 8 /MOD _col! ( a coff )
-    _xinc _data@ DROP SWAP
-    FNTH 0 DO ( coff a )
+: _atrow! ( pos -- ) COLS / FNTH 1+ * _row! ;
+: _tocol ( pos -- col off ) COLS MOD FNTW 1+ * 8 /MOD ;
+: CELL! ( g pos -- )
+    DUP _atrow! DUP _tocol _col! ROT ( pos coff g )
+    FNTH * ~FNT + ( pos coff a )
+    _xinc _data@ DROP
+    FNTH 0 DO ( pos coff a )
         C@+ 2 PICK 8 -^ LSHIFT
         _data@ 8 LSHIFT OR
         LCD_BUF I + 2DUP FNTH + C!
         SWAP 8 RSHIFT SWAP C!
     LOOP 2DROP
-    LCD_CURY C@ _row!
+    DUP _atrow!
     FNTH 0 DO LCD_BUF I + C@ _data! LOOP
-    LCD_CURY C@ _row! LCD_CURX C@ 8 / 1+ _col!
-    FNTH 0 DO LCD_BUF FNTH + I + C@ _data! LOOP
-    LCD_CURX C@ FNTW + 1+ DUP LCD_CURX C! ( x )
-    96 FNTW - > IF _lf THEN ;
+    DUP _atrow! _tocol NIP 1+ _col!
+    FNTH 0 DO LCD_BUF FNTH + I + C@ _data! LOOP ;

arch/z80/ti84/blk/610

@@ -1,4 +0,0 @@
-: (emit)
-    DUP 0xd = IF DROP _lf EXIT THEN
-    DUP 0x20 0x7e =><= NOT IF DROP EXIT THEN
-    0x20 - FNTH * ~FNT + _glyph> ;

arch/z80/ti84/xcomp.fs

@@ -3,7 +3,8 @@
 RS_ADDR 0x80 - CONSTANT SYSVARS
 0x8000 CONSTANT HERESTART
 SYSVARS 0x70 + CONSTANT LCD_MEM
-SYSVARS 0x72 + CONSTANT KBD_MEM
+SYSVARS 0x72 + CONSTANT GRID_MEM
+SYSVARS 0x74 + CONSTANT KBD_MEM
 0x01 CONSTANT KBD_PORT
 5 LOAD  ( z80 assembler )
 : ZFILL, ( u ) 0 DO 0 A, LOOP ;
@@ -64,7 +65,8 @@ CURRENT @ XCURRENT !
 283 335 LOADR ( boot.z80 )
 353 LOAD  ( xcomp core low )
 CREATE ~FNT CPFNT3x5
-605 610 LOADR ( LCD low )
+605 609 LOADR ( LCD low )
+402 403 LOADR ( Grid )
 616 620 LOADR ( KBD low )
 390 LOAD  ( xcomp core high )
 (entry) _

blk/263

@@ -7,7 +7,8 @@ CREATE XCURRENT 0 ,
     DUP ORG @ > IF ORG @ - BIN( @ + THEN ;
 : XFIND XCURRENT @ SWAP _find DROP _xapply ;
 : XLITN LIT" (n)" XFIND , , ;
-: X' XCON ' XCOFF ; : X['] XCON ' _xapply XLITN XCOFF ;
+: X' XCON ' XCOFF ; : X'? XCON '? XCOFF ;
+: X['] XCON ' _xapply XLITN XCOFF ;
 : XCOMPILE XCON ' _xapply XLITN
     LIT" ," FIND DROP _xapply , XCOFF ;
 : X[COMPILE] XCON ' _xapply , XCOFF ;

blk/270

@@ -1,4 +1,5 @@
 : CODE XCODE ;
+: '? X'? ;
 : ['] X['] ; IMMEDIATE
 : COMPILE XCOMPILE ; IMMEDIATE
 : [COMPILE] X[COMPILE] ; IMMEDIATE

blk/402

@@ -1,11 +1,11 @@
 : XYPOS [ GRID_MEM LITN ] ;
 : _cl* COLS LINES * ;
 : AT-XY ( x y -- ) LINES * + _cl* MOD XYPOS ! ;
-'? CLRLN NIP NOT [IF]
-: CLRLN ( ln -- ) COLS * DUP COLS + SWAP DO 0 I CELL! LOOP ;
+'? NEWLN NIP NOT [IF]
+: NEWLN ( ln -- ) COLS * DUP COLS + SWAP DO 0 I CELL! LOOP ;
 [THEN]
 : _lf
-    XYPOS @ COLS / 1+ DUP CLRLN
-    COLS * _cl* MOD XYPOS ! ;
+    XYPOS @ COLS / 1+ LINES MOD DUP NEWLN
+    COLS * XYPOS ! ;
 : _bs 0 ( blank ) XYPOS @ TUCK CELL! ( pos ) 1-
     _cl* MOD XYPOS ! ;

doc/protocol.txt

@@ -47,7 +47,7 @@ LINES     -- n     Number of lines in the device
 CELL!     g pos -- Set glyph at pos
 
 Optional:
-CLRLN     ln --    Clear line number ln.
+NEWLN     ln --    "Enter" line ln
 
 "pos" is a simple number (y * cols) + x. For example, if we
 have 40 columns per line, the position (x, y) (12, 10) is 412.
@@ -57,6 +57,15 @@ number of glyphs in the font, it's up to CELL! to ignore it.
 
 Glyph 0 is always blank.
 
-If CLRLN is not defined, the grid system uses multiple CELL!
+NEWLN is called when we "enter" a new line, that is, when we
+overflow from previous line or when 0x0d ( ASCII CR ) is emit-
+ted.
+
+When this is called, the line being entered should be cleared
+of its contents. On some systems, some kinf of screen offset
+might be have to be set to give a "scrolling" effect. Now's the
+time.
+
+If it's not defined, the grid system uses multiple CELL!
 calls to clear it. On some devices, this is highly inefficient.
-Drivers for those devices should define CLRLN.
+Drivers for those devices should define NEWLINE.