diff --git a/devices/pc8080/machine/invaders/README.md b/devices/pc8080/machine/invaders/README.md
index 48495f194..bfbc9b4f5 100644
--- a/devices/pc8080/machine/invaders/README.md
+++ b/devices/pc8080/machine/invaders/README.md
@@ -12,7 +12,7 @@ machines:
 Space Invaders (Under Construction)
 ---
 
-This is the first test of [PC8080](/modules/pc8080/), a new 8080-based machine emulator being added to the
+This is a test of [PC8080](/modules/pc8080/), a new 8080-based machine emulator being added to the
 PCjs Project.  It's a work-in-progress, so there's not much to look at yet.  And the goal is not to build
 yet-another Space Invaders/Arcade Machine emulator -- that's been done many times over -- but to start with
 a well-understood 8080-based machine architecture that doesn't need a lot of peripherals, and use it as the
diff --git a/devices/pc8080/machine/test/README.md b/devices/pc8080/machine/test/README.md
index c662651c4..02c03d3f0 100644
--- a/devices/pc8080/machine/test/README.md
+++ b/devices/pc8080/machine/test/README.md
@@ -11,4 +11,21 @@ machines:
 8080 Test Machine
 ---
 
+This is a test of [PC8080](/modules/pc8080/), a new 8080-based machine emulator being added to the
+PCjs Project.
+
+This test machine loads a copy of the
+[8080 Exerciser](https://web.archive.org/web/20151006085348/http://www.idb.me.uk/sunhillow/8080.html)
+(specifically, [8080EX1](/devices/pc8080/rom/test/8080EX1.MAC)) and intercepts *just* enough of the exerciser's
+CP/M calls to display its progress.
+
+The good news: PC8080 passes all the 8080 Exerciser tests.  At 2Mhz, the tests do take quite a while,
+but you can click the speed button while the machine is running to increase the simulated speed; it will
+wrap around to 2Mhz if you try to exceed the maximum speed that your system supports.
+
+NOTE: The original [8080 Exerciser website](http://www.idb.me.uk/sunhillow/8080.html) is currently unavailable,
+so we refer you to the copy on
+[archive.org](https://web.archive.org/web/20151006085348/http://www.idb.me.uk/sunhillow/8080.html).
+The 8080 Exerciser has also been "forked" on [GitHub](https://github.com/begoon/8080ex1).
+
 {% include machine.html id="test8080" %}
diff --git a/modules/htmlout/lib/htmlout.js b/modules/htmlout/lib/htmlout.js
index 421ed9c72..445d6d28d 100644
--- a/modules/htmlout/lib/htmlout.js
+++ b/modules/htmlout/lib/htmlout.js
@@ -186,7 +186,8 @@ var asNonDirectories = [
 ];
 
 /*
- * A list of plain-text file types that we want the server to serve up with mime-type "text/plain".
+ * A list of plain-text file types that we want the server to serve up with mime-type "text/plain";
+ * all extensions are lower-cased before being checked.
  */
 var asExtsPlainText = [
     "65v",
@@ -194,6 +195,7 @@ var asExtsPlainText = [
     "bas",
     "hex",
     "inc",
+    "mac",
     "map",
     "nasm",
     "txt"
diff --git a/modules/pc8080/README.md b/modules/pc8080/README.md
index aad8c7275..7ff058655 100644
--- a/modules/pc8080/README.md
+++ b/modules/pc8080/README.md
@@ -26,6 +26,7 @@ PC8080 is currently comprised of the following non-shared components, as listed
 * [cpu.js](/modules/pc8080/lib/cpu.js)
 * [cpusim.js](/modules/pc8080/lib/cpusim.js)
 * [cpuops.js](/modules/pc8080/lib/cpuops.js)
+* [chipset.js](/modules/pc8080/lib/chipset.js)
 * [rom.js](/modules/pc8080/lib/rom.js)
 * [ram.js](/modules/pc8080/lib/ram.js)
 * [keyboard.js](/modules/pc8080/lib/keyboard.js)