Update README.md

Author: 0neblock

README.md

@@ -29,6 +29,8 @@ This is a fully-compliant SNMPv2c Agent built for Arduino's, but will work on an
   * SNMPv2 Trap
 
 It was designed and tested around an ESP32, but will work with any Arduino-based devied that has a UDP object available.
+For non-ESP Arduino's, you will have to also include this library: https://github.com/mike-matera/ArduinoSTL
+Be careful when using this library on non-ESP Arduino's as they're limited on memory. Try to keep the amount of OID's you add to a minimum.
 
 The example goes into detail around how to use, or look at `src/SNMP_Agent.h` for the API.
 
@@ -170,4 +172,4 @@ There is currencly no mechanism to know (with code) if an SNMP INFORM request ha
 
 I am working on adding the functionality to act as an SNMP Server or Manager. In the meantime, if you need to do this, look at the library here: https://github.com/shortbloke/Arduino_SNMP_Manager
 
-Pull requests/comments are welcome
+Pull requests/comments are welcome