diff --git a/README.md b/README.md
index 2ef1832..547389d 100644
--- a/README.md
+++ b/README.md
@@ -1,21 +1,22 @@
-# Pololu USB AVR Programmer v2 software
+# Pololu USB AVR Programmer v2.x software
 
 Version: 1.0.2<br/>
 Release date: 2016 May 05<br/>
 [www.pololu.com](https://www.pololu.com/)
 
 This repository contains the source code of the configuration software that
-supports the [Pololu USB AVR Programmer v2](https://www.pololu.com/product/3170).
+supports the [Pololu USB AVR Programmer v2](https://www.pololu.com/product/3170)
+and [Pololu USB AVR Programmer v2.1](https://www.pololu.com/product/3170).
 There are two programs: the Pololu USB AVR Programmer v2 Command-line Utility
 (pavr2cmd) and the Pololu USB AVR Programmer v2 Configuration Utility (pavr2gui).
 
-This software only supports the Pololu USB AVR Programmer *v2*, which is
-*blue-colored* and labeled *pgm04a*.  If you have an older Pololu programmer,
+This software only supports the Pololu USB AVR Programmer *v2* and *v2.1*,
+which are *blue-colored*.  If you have an older Pololu programmer,
 refer to the product page and user's guide of that programmer for software
 resources.
 
-Note that the *v2* in the name of this repository refers to the version of the
-hardware product, which is different from the version number of this software.
+Note that the *v2.x* in the name of this repository refers to the versions of the
+hardware products, which is different from the version number of this software.
 
 This software is only used for configuring the programmer and reading
 information from it.  To actually program an AVR, you will need AVR programming
@@ -24,7 +25,7 @@ software such as AVRDUDE or Atmel Studio.
 ## Installation
 
 Installers for Windows and Mac OS X are available for download from the Pololu
-USB AVR Programmer v2 User's Guide:
+USB AVR Programmer v2.x User's Guide:
 
   http://www.pololu.com/docs/0J67
 
diff --git a/lib/programmer.cpp b/lib/programmer.cpp
index 7506d62..c5bfe2b 100644
--- a/lib/programmer.cpp
+++ b/lib/programmer.cpp
@@ -11,8 +11,8 @@
 // A descriptor type from USB 2.0 Table 9-5
 #define USB_DESCRIPTOR_TYPE_STRING 3
 
-// pgm04a uses voltage units of 32 mV, so the maximum representable voltage
-// is 8160 mV.
+// The programmer uses voltage units of 32 mV, so the maximum representable
+// voltage is 8160 mV.
 static const uint32_t maxRepresentableVoltage = 255 * PAVR2_VOLTAGE_UNITS;
 #if PAVR2_VOLTAGE_UNITS == 32
 #define MAX_REPRESENTABLE_VOLTAGE_STR "8160 mV"
diff --git a/mac-installer/welcome.html.in b/mac-installer/welcome.html.in
index ed9d9b4..4b82734 100644
--- a/mac-installer/welcome.html.in
+++ b/mac-installer/welcome.html.in
@@ -7,13 +7,14 @@ body { font-family: sans-serif; }
 <p>
 
 This package installs the configuration software for the <b>Pololu USB AVR
-Programmer v2</b> on your computer. Please note that <b>v2</b> is the version of the
-hardware product.  The version number of this software is ${SOFTWARE_VERSION}.
+Programmer v2.x</b> on your computer. Please note that <b>v2.x</b> refers to the
+the versions of the hardware products.
+The version number of this software is ${SOFTWARE_VERSION}.
 
 <p>
 
-This software only supports the Pololu USB AVR Programmer <b>v2</b>, which is
-<b>blue-colored</b> and labeled <b>pgm04a</b>.  If you have an older Pololu
+This software only supports the Pololu USB AVR Programmer <b>v2</b> and <b>v2.1</b>,
+which are <b>blue-colored</b>.  If you have an older Pololu
 programmer, refer to the product page and user's guide of that programmer for
 software.