diff --git a/library.json b/library.json
index 8c51e55..5419d6f 100644
--- a/library.json
+++ b/library.json
@@ -10,7 +10,7 @@
         "url": "https://github.com/M5Stack/M5StamPLC.git"
     },
     "dependencies": {
-        "M5Unified": "*",
+        "M5Unified": ">=0.2.21",
         "M5GFX": "*"
     },
     "version": "1.2.0",
diff --git a/library.properties b/library.properties
index 87c2f0f..f0754ff 100644
--- a/library.properties
+++ b/library.properties
@@ -8,4 +8,4 @@ category=Device Control
 url=https://github.com/m5stack/M5StamPLC.git
 architectures=esp32
 includes=src,src/utils
-depends=M5Unified
\ No newline at end of file
+depends=M5Unified (>=0.2.21)
\ No newline at end of file
diff --git a/src/M5StamPLC.cpp b/src/M5StamPLC.cpp
index b8a76c7..ef937e5 100644
--- a/src/M5StamPLC.cpp
+++ b/src/M5StamPLC.cpp
@@ -61,15 +61,15 @@ void M5_STAMPLC::io_expander_a_init()
 
     // Status light init
     ioe.setDirection(4, true);
-    ioe.setPullMode(4, false);
+    ioe.setPullMode(4, m5::IOExpander_Base::pull_down);
     ioe.setHighImpedance(4, true);
 
     ioe.setDirection(5, true);
-    ioe.setPullMode(5, false);
+    ioe.setPullMode(5, m5::IOExpander_Base::pull_down);
     ioe.setHighImpedance(5, true);
 
     ioe.setDirection(6, true);
-    ioe.setPullMode(6, false);
+    ioe.setPullMode(6, m5::IOExpander_Base::pull_down);
     ioe.setHighImpedance(6, true);
 
     ioe.resetIrq();
diff --git a/src/modules/M5StamPLC_AC.cpp b/src/modules/M5StamPLC_AC.cpp
index 2d70426..af20e81 100644
--- a/src/modules/M5StamPLC_AC.cpp
+++ b/src/modules/M5StamPLC_AC.cpp
@@ -32,13 +32,13 @@ bool M5StamPLC_AC::begin()
 
     // AC relay
     _ioe->setDirection(_pin_relay, true);
-    _ioe->setPullMode(_pin_relay, false);
+    _ioe->setPullMode(_pin_relay, m5::IOExpander_Base::pull_down);
     _ioe->setHighImpedance(_pin_relay, false);
 
     // Status light
     auto setup_status_light_pin = [](m5::PI4IOE5V6408_Class* ioe, uint8_t pin) {
         ioe->setDirection(pin, true);
-        ioe->setPullMode(pin, true);
+        ioe->setPullMode(pin, m5::IOExpander_Base::pull_up);
         ioe->setHighImpedance(pin, false);
         ioe->digitalWrite(pin, true);
     };