ps2: add shift support

blk/001

@@ -6,6 +6,7 @@ MASTER INDEX
 150 Extra words
 200 Z80 assembler             260 Cross compilation
 280 Z80 boot code             350 Core words
+410 PS/2 keyboard subsystem
 490 TRS-80 Recipe             520 Fonts
 550 TI-84+ Recipe             580 RC2014 Recipe
 620 Sega Master System Recipe

blk/410

@@ -0,0 +1,11 @@
+PS/2 keyboard subsystem
+
+Provides (key) from a driver providing (ps2kc). That is, for a
+driver taking care of providing all key codes emanating from a
+PS/2 keyboard, this subsystem takes care of mapping those key-
+strokes to ASCII characters. This code is designed to be cross-
+compiled and loaded with drivers.
+
+Requires PS2_MEM to be defined.
+
+Load range: 411-414

blk/411

@@ -0,0 +1,14 @@
+: PS2_SHIFT [ PS2_MEM LITN ] ;
+: PS2$ 0 PS2_SHIFT C! ;
+
+( A list of the values associated with the 0x80 possible scan
+codes of the set 2 of the PS/2 keyboard specs. 0 means no
+value. That value is a character that can be read in (key)
+No make code in the PS/2 set 2 reaches 0x80. )
+CREATE PS2_CODES
+( 00 ) 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 0 C,
+( 08 ) 0 C, 0 C, 0 C, 0 C, 0 C, 9 C, '`' C, 0 C,
+( 10 ) 0 C, 0 C, 0 C, 0 C, 0 C, 'q' C, '1' C, 0 C,
+( 18 ) 0 C, 0 C, 'z' C, 's' C, 'a' C, 'w' C, '2' C, 0 C,
+( 20 ) 0 C, 'c' C, 'x' C, 'd' C, 'e' C, '4' C, '3' C, 0 C,
+( 28 ) 0 C, 32 C, 'v' C, 'f' C, 't' C, 'r' C, '5' C, 0 C,

blk/412

@@ -0,0 +1,16 @@
+( 30 ) 0 C, 'n' C, 'b' C, 'h' C, 'g' C, 'y' C, '6' C, 0 C,
+( 38 ) 0 C, 0 C, 'm' C, 'j' C, 'u' C, '7' C, '8' C, 0 C,
+( 40 ) 0 C, ',' C, 'k' C, 'i' C, 'o' C, '0' C, '9' C, 0 C,
+( 48 ) 0 C, '.' C, '/' C, 'l' C, ';' C, 'p' C, '-' C, 0 C,
+( 50 ) 0 C, 0 C, ''' C, 0 C, '[' C, '=' C, 0 C, 0 C,
+( 58 ) 0 C, 0 C, 13 C, ']' C, 0 C, '\' C, 0 C, 0 C,
+( 60 ) 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 8 C, 0 C,
+( 68 ) 0 C, '1' C, 0 C, '4' C, '7' C, 0 C, 0 C, 0 C,
+( 70 ) '0' C, '.' C, '2' C, '5' C, '6' C, '8' C, 27 C, 0 C,
+( 78 ) 0 C, 0 C, '3' C, 0 C, 0 C, '9' C, 0 C, 0 C,
+( Same values, but shifted )
+( 00 ) 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 0 C,
+( 08 ) 0 C, 0 C, 0 C, 0 C, 0 C, 9 C, '~' C, 0 C,
+( 10 ) 0 C, 0 C, 0 C, 0 C, 0 C, 'Q' C, '!' C, 0 C,
+( 18 ) 0 C, 0 C, 'Z' C, 'S' C, 'A' C, 'W' C, '@' C, 0 C,
+( 20 ) 0 C, 'C' C, 'X' C, 'D' C, 'E' C, '$' C, '#' C, 0 C,

blk/413

@@ -0,0 +1,12 @@
+( 28 ) 0 C, 32 C, 'V' C, 'F' C, 'T' C, 'R' C, '%' C, 0 C,
+( 30 ) 0 C, 'N' C, 'B' C, 'H' C, 'G' C, 'Y' C, '^' C, 0 C,
+( 38 ) 0 C, 0 C, 'M' C, 'J' C, 'U' C, '&' C, '*' C, 0 C,
+( 40 ) 0 C, '<' C, 'K' C, 'I' C, 'O' C, ')' C, '(' C, 0 C,
+( 48 ) 0 C, '>' C, '?' C, 'L' C, ':' C, 'P' C, '_' C, 0 C,
+( 50 ) 0 C, 0 C, '"' C, 0 C, '{' C, '+' C, 0 C, 0 C,
+( 58 ) 0 C, 0 C, 13 C, '}' C, 0 C, '|' C, 0 C, 0 C,
+( 60 ) 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 8 C, 0 C,
+( 68 ) 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 0 C,
+( 70 ) 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 27 C, 0 C,
+( 78 ) 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 0 C, 0 C,
+

blk/414

@@ -0,0 +1,15 @@
+: _shift? ( kc -- f ) DUP 0x12 = SWAP 0x59 = OR ;
+: _get ( -- kc ) 0 ( dummy ) BEGIN DROP (ps2kc) DUP UNTIL ;
+: (key) _get
+    DUP 0xe0 ( extended ) = IF ( ignore ) DROP (key) EXIT THEN
+    DUP 0xf0 ( break ) = IF DROP ( )
+        ( get next kc and see if it's a shift )
+        _get _shift? IF ( drop shift ) 0 PS2_SHIFT C! THEN
+        ( whether we had a shift or not, we return the next )
+        (key) EXIT THEN
+    DUP 0x7f > IF DROP (key) EXIT THEN
+    DUP _shift? IF DROP 1 PS2_SHIFT C! (key) EXIT THEN
+    ( ah, finally, we have a gentle run-of-the-mill KC )
+    PS2_CODES PS2_SHIFT @ IF 0x80 + THEN + C@
+    DUP NOT IF DROP (key) THEN ;
+