diff --git a/src/handler/matrix_display.py b/src/handler/matrix_display.py
index db79cf6..1355661 100644
--- a/src/handler/matrix_display.py
+++ b/src/handler/matrix_display.py
@@ -68,7 +68,7 @@ class MatrixDisplay:
         with canvas(self.device) as draw:
             draw.rectangle((0, 0, 31, 7), outline="white", fill="white")
 
-    async def pattern(self, pattern: str = "0,1", off_ms: int = 500, on_ms: int = 500):
+    async def pattern(self, pattern: str = "0,1", step_ms: int = 500):
         # Parse
         pattern_steps = [step.strip() == "1" for step in pattern.split(",") if step]
         # Execute
@@ -77,7 +77,7 @@ class MatrixDisplay:
                 self.turn_full()
             else:
                 self.turn_off()
-            await asyncio.sleep((on_ms if step else off_ms) / 1000)
+            await asyncio.sleep(step_ms / 1000)
 
     def show_current_time(self):
         self.device.contrast(self.contrast)
diff --git a/src/main.py b/src/main.py
index 4669cb6..623e458 100644
--- a/src/main.py
+++ b/src/main.py
@@ -97,10 +97,8 @@ async def flash(count: int = 1, contrast: Optional[int] = None):
 
 
 @app.post("/pattern")
-async def flash(pattern: str="0,1", off_ms: int = 500, on_ms: int = 500):
-    await queue.set_idle_action(
-        display_pattern, pattern=pattern, off_ms=off_ms, on_ms=on_ms
-    )
+async def flash(pattern: str = "0,1", step_ms: int = 500):
+    await queue.set_idle_action(display_pattern, pattern=pattern, step_ms=step_ms)
     return {"message": "Activated pattern."}