Merge branch 'issue/382' into develop (fixes #382)

uccser · Oct 11, 2016 · d6382f9 · d6382f9
2 parents b7a08d9 + e53bd12
commit d6382f9
Show file tree

Hide file tree

Showing 2 changed files with 6 additions and 1 deletion.
diff --git a/interactives/mips-assembler/index.php b/interactives/mips-assembler/index.php
@@ -582,7 +582,7 @@ function trim_self(&$string) { $string = trim($string); }
         <div class="col s12 l6">
 
           <h4>MIPS Input</h4>
-          <p>Please enter MIPS code below to see the assembler output. A subset of MIPS is implemented. Comments start with #.</p>
+          <p>Please enter MIPS code below to see the assembler output. <strong>Note:</strong> Only a subset of MIPS is implemented, and negative values will be read as zero. Comments start with #.</p>
 
           <?php print '<form action="'.$_ENV['SCRIPT_URL'].'" method="post">'; ?>
 <textarea name="input" id="mips_input" class="code"><?php

diff --git a/interactives/mips-simulator/index.php b/interactives/mips-simulator/index.php
@@ -382,6 +382,11 @@ function smartbindec($bin) {
                            hexdec($reg->read($instr->rtdec)) * pow(2,$instr->shamtdec)
                            );
                        break;
+                   case 0x22: //subtract
+                       $reg->write($instr->rddec,
+                           smarthexdec($reg->read($instr->rsdec)) - smarthexdec($reg->read($instr->rtdec))
+                           );
+                       break;
                    case 0x2: // srl
 
                        break;