diff --git a/MERCURY_ITC/iocBoot/iocMERCURY-IOC-01/config.xml b/MERCURY_ITC/iocBoot/iocMERCURY-IOC-01/config.xml
index 37ce876c4..7549754ef 100644
--- a/MERCURY_ITC/iocBoot/iocMERCURY-IOC-01/config.xml
+++ b/MERCURY_ITC/iocBoot/iocMERCURY-IOC-01/config.xml
@@ -14,6 +14,9 @@
 <macro name="PRESSURE_1" pattern="^.*[.].*$" description="Card identifier for Pressure 1 (e.g. DB1.P1). Blank for no controller." hasDefault="YES" defaultValue="" />
 <macro name="PRESSURE_2" pattern="^.*[.].*$" description="Card identifier for Pressure 2 (e.g. DB1.P1). Blank for no controller." hasDefault="YES" defaultValue="" />
 
+<macro name="IPADDR" pattern="^.*$" description="IP Address for Ethernet comms" hasDefault="YES" defaultValue="" />
+<macro name="IPPORT" pattern="^.*$" description="IP Port for Ethernet comms" hasDefault="YES" defaultValue="7020" />
+
 <macro name="SPC_TYPE_1" pattern="^(FLOW|VTI|NONE)$" description="Software pressure control method to use on Temperature 1" hasDefault="YES" defaultValue="NONE" />
 <macro name="SPC_TYPE_2" pattern="^(FLOW|VTI|NONE)$" description="Software pressure control method to use on Temperature 2" hasDefault="YES" defaultValue="NONE" />
 <macro name="SPC_TYPE_3" pattern="^(FLOW|VTI|NONE)$" description="Software pressure control method to use on Temperature 3" hasDefault="YES" defaultValue="NONE" />
diff --git a/MERCURY_ITC/iocBoot/iocMERCURY-IOC-01/st-common.cmd b/MERCURY_ITC/iocBoot/iocMERCURY-IOC-01/st-common.cmd
index 6160a9fa5..ff2f7ef98 100644
--- a/MERCURY_ITC/iocBoot/iocMERCURY-IOC-01/st-common.cmd
+++ b/MERCURY_ITC/iocBoot/iocMERCURY-IOC-01/st-common.cmd
@@ -13,18 +13,21 @@ $(IFRECSIM) drvAsynSerialPortConfigure("L0", "$(PORT=NUL)", 0, 1, 0, 0)
 # For dev sim devices
 $(IFDEVSIM) drvAsynIPPortConfigure("L0", "localhost:$(EMULATOR_PORT=57677)")
 
-## For real device use:
-$(IFNOTDEVSIM) $(IFNOTRECSIM) drvAsynSerialPortConfigure("L0", "$(PORT)", 0, 0, 0, 0)
-$(IFNOTDEVSIM) $(IFNOTRECSIM) asynSetOption("L0", -1, "baud", "$(BAUD=57600)")
-$(IFNOTDEVSIM) $(IFNOTRECSIM) asynSetOption("L0", -1, "bits", "$(BITS=8)")
-$(IFNOTDEVSIM) $(IFNOTRECSIM) asynSetOption("L0", -1, "parity", "$(PARITY=none)")
-$(IFNOTDEVSIM) $(IFNOTRECSIM) asynSetOption("L0", -1, "stop", "$(STOP=2)")
-
-## Flow control off
-$(IFNOTDEVSIM) $(IFNOTRECSIM) asynSetOption("L0", 0, "clocal", "Y")
-$(IFNOTDEVSIM) $(IFNOTRECSIM) asynSetOption("L0",0,"crtscts","N")
-$(IFNOTDEVSIM) $(IFNOTRECSIM) asynSetOption("L0",0,"ixon","N")
-$(IFNOTDEVSIM) $(IFNOTRECSIM) asynSetOption("L0",0,"ixoff","N")
+stringiftest("IPADDR", "$(IPADDR=)", 0x2)
+
+## If serial comms mode
+$(IFNOTDEVSIM) $(IFNOTRECSIM) $(IFNOTIPADDR) drvAsynSerialPortConfigure("L0", "$(PORT)", 0, 0, 0, 0)
+$(IFNOTDEVSIM) $(IFNOTRECSIM) $(IFNOTIPADDR) asynSetOption("L0", -1, "baud", "$(BAUD=57600)")
+$(IFNOTDEVSIM) $(IFNOTRECSIM) $(IFNOTIPADDR) asynSetOption("L0", -1, "bits", "$(BITS=8)")
+$(IFNOTDEVSIM) $(IFNOTRECSIM) $(IFNOTIPADDR) asynSetOption("L0", -1, "parity", "$(PARITY=none)")
+$(IFNOTDEVSIM) $(IFNOTRECSIM) $(IFNOTIPADDR) asynSetOption("L0", -1, "stop", "$(STOP=2)")
+$(IFNOTDEVSIM) $(IFNOTRECSIM) $(IFNOTIPADDR) asynSetOption("L0", 0, "clocal", "Y")
+$(IFNOTDEVSIM) $(IFNOTRECSIM) $(IFNOTIPADDR) asynSetOption("L0",0,"crtscts","N")
+$(IFNOTDEVSIM) $(IFNOTRECSIM) $(IFNOTIPADDR) asynSetOption("L0",0,"ixon","N")
+$(IFNOTDEVSIM) $(IFNOTRECSIM) $(IFNOTIPADDR) asynSetOption("L0",0,"ixoff","N")
+
+## If ethernet comms mode
+$(IFNOTDEVSIM) $(IFNOTRECSIM) $(IFIPADDR) drvAsynIPPortConfigure("L0", "$(IPADDR=):$(IPPORT=7020)")
 
 ## Load record instances