check recv size

adafruit_wiznet5k/adafruit_wiznet5k.py

@@ -178,6 +178,7 @@ def __init__(
         self.mac_address = mac
         self.src_port = 0
         self._dns = 0
+
         # Set DHCP
         self._dhcp_client = None
         if is_dhcp:
@@ -196,6 +197,17 @@ def set_dhcp(self, hostname=None, response_timeout=30):
         """
         if self._debug:
             print("* Initializing DHCP")
+
+        # First, wait link status is on
+        # to avoid the code during DHCP - assert self.link_status, "Ethernet cable disconnected!"
+        start_time = time.monotonic()
+        while True:
+            if self.link_status or ((time.monotonic() - start_time) > 5):
+                break
+            time.sleep(1)
+            if self._debug:
+                print("My Link is:", self.link_status)
+
         # Return IP assigned by DHCP
         self._dhcp_client = dhcp.DHCP(
             self, self.mac_address, hostname, response_timeout, debug=self._debug

examples/wiznet5k_simpleserver.py

@@ -28,9 +28,10 @@
 server.bind((server_ip, server_port))  # Bind to IP and Port
 server.listen()  # Begin listening for incoming clients
 
+conn, addr = server.accept()  # Wait for a connection from a client.
 while True:
-    conn, addr = server.accept()  # Wait for a connection from a client.
     with conn:
-        data = conn.recv()
-        print(data)
-        conn.send(data)  # Echo message back to client
+        data = conn.recv(1024)
+        if data:  # Wait for receiving data
+            print(data)
+            conn.send(data)  # Echo message back to client