diff --git a/.gitmodules b/.gitmodules
index cd0c6fd..a1ed903 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -10,3 +10,6 @@
 [submodule "lib/zh_avr_common"]
 	path = lib/zh_avr_common
 	url = http://git.zh.com.ru/avr_libraries/zh_avr_common
+[submodule "lib/zh_avr_pcf8574"]
+	path = lib/zh_avr_pcf8574
+	url = http://git.zh.com.ru/avr_libraries/zh_avr_pcf8574
diff --git a/lib/zh_avr_pcf8574 b/lib/zh_avr_pcf8574
new file mode 160000
index 0000000..8c6460a
--- /dev/null
+++ b/lib/zh_avr_pcf8574
@@ -0,0 +1 @@
+Subproject commit 8c6460a1d174dc2feb6c12b1432e8affc643ae07