--- vt102/vt102	2014/12/03 02:16:45	1.18
+++ vt102/vt102	2014/12/03 02:40:34	1.19
@@ -29,10 +29,17 @@
 shift                           if $ARGV[0] =~ /^-?-vt102$/;
 shift, ($VT131 = 1)             if $ARGV[0] =~ /^-?-vt131$/;
 
+# vt100 wps = word processing roms
+# vt101 = vt102 - avo, but custom rom? really?
+# vt103 = vt100 + tu58 tape drive
+# vt125 = vt100 + gpo graphics processor
+# vt132 = vt100 + avo, stp
+# vt180 = vt100 + z80 cp/m
+
 if ($ARGV[0] =~ /^-/) {
    die <<EOF;
 
-VT102, A VT100/101/102/131 SIMULATOR
+VT102, A VT100/102/131 SIMULATOR
 
 Usage:
 
@@ -401,9 +408,9 @@
 # possible todo: optimize ora a, maybe xra a
 
 $op[0xc6] = 'sf  $A += IMM8'; # adi
-# ce ADI NYI
+# ce ACI NYI, apparently unused
 $op[0xd6] = 'sf  $A -= IMM8'; # sui
-# de SBI NYI
+# de SBI NYI, apparently unused
 $op[0xe6] = 'sf8 $A &= IMM8'; # ani
 $op[0xee] = 'sf8 $A ^= IMM8'; # xri
 $op[0xf6] = 'sf8 $A |= IMM8'; # ori
@@ -431,7 +438,7 @@
 $op[0xc7 + $_ * 8] = "JMP $_ * 8" for 0..7; # rst
 
 $op[0xe9] = 'JMP $H * 256 + $L'; # pchl
-# f9 SPHL NYI
+# f9 SPHL NYI, apparently unused
 
 $op[0x37] = '$FC = 1   '; # stc
 $op[0x3f] = '$FC = !$FC'; # cmc
@@ -441,7 +448,7 @@
 
 $op[0xeb] = '($D, $E, $H, $L) = ($H, $L, $D, $E)'; # xchg
  
-# e3 xthl NYI # @ 917b, hl <-> (sp)
+# e3 xthl NYI # @ 917b in e69, hl <-> (sp)
 
 $op[0x20] = '$A = $INTPEND * 16 + $INTMASK + ($IFF && 8)'; # rim (incomplete)
 $op[0x30] = '$INTMASK = $A & 7 if $A & 8'; # sim (incomplete)