diff --git a/doc/notes.txt b/doc/notes.txt
index 7b3518c0..9c721d5a 100644
--- a/doc/notes.txt
+++ b/doc/notes.txt
@@ -106,7 +106,6 @@ TODO:
 - debug highlight doesn't go away when debugging -> running
   - show breakpoint of PC or highest address on stack
   - can we highlight line instead of select?
-- replay doesn't work for nes (force background tile redraw)
 - running profiler while replaying? grand unified replay?
 - click on profiler to step to position
   - breakpoints stop profiler from running
@@ -126,7 +125,10 @@ TODO:
 - single-stepping vector games makes screen fade
 - break on stack overflow, bad op, bad access, etc
 - PPU/TIA register write visualization
-- nes debug view toolbar
+- nes
+  - replay doesn't work for nes (force background tile redraw)
+  - nes debug view toolbar
+  - support NES_HEADER_16K?
 - vcs sound continues when paused
 - upload multiple files/zip file to subdirectory
   - allow "include graphics.asm" instead of "include project/graphics.asm"
@@ -153,6 +155,8 @@ TODO:
   - build ca65 projects? https://github.com/pinobatch/thwaite-nes/blob/master/makefile
   - switching platform of a repo?
   - retaining repo_id in localstorage?
+  - don't like alert() after pushing
+  - should have a preview of commit
 
 
 WEB WORKER FORMAT
@@ -288,3 +292,13 @@ Pull
 Push
 
 Git metadata kept in local storage
+
+Converting from NESASM to DASM
+
+- subroutine keyword on labels
+- [zp],y to (zp),y
+- asl a -> asl
+- LOW(x) and HIGH(x) to <() and >()
+- .db to .byte, .dw to .word
+- use NES_HEADER macros
+- no .bank
diff --git a/src/platform/nes.ts b/src/platform/nes.ts
index ecca5f58..34cd5416 100644
--- a/src/platform/nes.ts
+++ b/src/platform/nes.ts
@@ -374,6 +374,10 @@ class JSNESPlatform extends Base6502Platform implements Platform {
     s += "\n";
     return s;
   }
+  getToolForFilename = (fn:string) : string => {
+    if (fn.endsWith(".asm")) return "ca65"; // .asm uses ca65
+    else return getToolForFilename_6502(fn);
+  }
 }
 
 /// MAME support
@@ -407,8 +411,8 @@ class NESMAMEPlatform extends BaseMAMEPlatform implements Platform {
   }
 
   getPresets() { return JSNES_PRESETS; }
-  getOpcodeMetadata = getOpcodeMetadata_6502;
   getToolForFilename = getToolForFilename_6502;
+  getOpcodeMetadata = getOpcodeMetadata_6502;
   getDefaultExtension() { return ".c"; };
 }
 
diff --git a/src/worker/workermain.ts b/src/worker/workermain.ts
index 3dcd49f7..4f507b16 100644
--- a/src/worker/workermain.ts
+++ b/src/worker/workermain.ts
@@ -645,6 +645,7 @@ function parseSourceLines(code:string, lineMatch, offsetMatch) {
 }
 
 function parseDASMListing(code:string, unresolved:{}, mainFilename:string) {
+  // TODO: this gets very slow
   //        4  08ee		       a9 00	   start      lda	#01workermain.js:23:5
   var lineMatch = /\s*(\d+)\s+(\S+)\s+([0-9a-f]+)\s+([?0-9a-f][?0-9a-f ]+)?\s+(.+)?/i;
   var equMatch = /\bequ\b/i;
@@ -702,13 +703,17 @@ function parseDASMListing(code:string, unresolved:{}, mainFilename:string) {
       // TODO: better symbol test (word boundaries)
       // TODO: ignore IFCONST and IFNCONST usage
       for (var key in unresolved) {
-        var pos = restline ? restline.indexOf(key) : line.indexOf(key);
+        var l = restline || line;
+        var pos = l.indexOf(key);
         if (pos >= 0) {
-          errors.push({
-            path:filename,
-            line:linenum,
-            msg:"Unresolved symbol '" + key + "'"
-          });
+          var cmt = l.indexOf(';');
+          if (cmt < 0 || cmt > pos) {
+            errors.push({
+              path:filename,
+              line:linenum,
+              msg:"Unresolved symbol '" + key + "'"
+            });
+          }
         }
       }
     }
diff --git a/test/cli/testworker.js b/test/cli/testworker.js
index dccb81c3..23c531df 100644
--- a/test/cli/testworker.js
+++ b/test/cli/testworker.js
@@ -81,7 +81,7 @@ describe('Worker', function() {
     compile('dasm', '\tprocessor 6502\n\torg $f000\nfoo lda #0\n', 'vcs', done, 2, 1);
   });
   it('should NOT assemble DASM', function(done) {
-    compile('dasm', '\tprocessor 6502\n\torg $f000\nfoo xxx #0\n', 'vcs', done, 0, 0, 1);
+    compile('dasm', '\tprocessor 6502\n\torg $f000 ; this is a comment\nfoo asl a\n', 'vcs', done, 0, 0, 1);
   });
   /*
   it('should assemble ACME', function(done) {