diff --git a/README.md b/README.md
index b919ff5..9a8c132 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,8 @@
 This library is a set of source files for AVR processors that provide functionality of use in amateur radio applications, although many of the files could also be used in 
 non-radio systems.
 
-They provide CAT control, display, EEPROM, I2C, LCD, millisecond timer, morse keyer, oscillator (si5351a), rotary control and serial support.
+They provide CAT control, display, EEPROM, I2C, LCD, millisecond timer, morse keyer, oscillator (si5351a), pushbutton, rotary control and serial support.
+
+They should work on most 8-bit AVR processors including the ATmega, ATtiny and tinyAVR 1-series.
 
 See [TARL documentation](https://g4tgj.github.io/TARLdocs) for how to use the library.