diff --git a/src/comet/emulator/thorlabs/pm100.py b/src/comet/emulator/thorlabs/pm100.py
index 778fc8f..c62f6bc 100644
--- a/src/comet/emulator/thorlabs/pm100.py
+++ b/src/comet/emulator/thorlabs/pm100.py
@@ -6,7 +6,6 @@
 from comet.emulator import message, run
 from comet.emulator.utils import Error
 
-
 __all__ = ["PM100Emulator"]
 
 
@@ -34,6 +33,10 @@ def set_reset(self) -> None:
     def set_clear(self) -> None:
         self.error_queue.clear()
 
+    @message(r"^\*OPC\?$")
+    def get_opc(self) -> int:
+        return 1
+
     @message(r"^:?SYST:ERR(?::NEXT)?\?$")
     def get_system_error_next(self) -> str:
         if self.error_queue: