diff --git a/mfrc522/MFRC522.py b/mfrc522/MFRC522.py
index 1698351..94388cf 100644
--- a/mfrc522/MFRC522.py
+++ b/mfrc522/MFRC522.py
@@ -214,6 +214,7 @@ def MFRC522_ToCard(self, command, sendData):
 
         i = 2000
         while True:
+            time.sleep(0.25)
             n = self.Read_MFRC522(self.CommIrqReg)
             i -= 1
             if ~((i != 0) and ~(n & 0x01) and ~(n & waitIRq)):