diff --git a/apps/cm/coder.py b/apps/cm/coder.py
index 095fa08f..360b63f7 100644
--- a/apps/cm/coder.py
+++ b/apps/cm/coder.py
@@ -27,15 +27,32 @@ class CoderClient:
         try:
             with socket.create_connection((self.ip, self.port), timeout=self.timeout) as s:
                 s.sendall(frame)
-                if not expect_reply:
-                    return b""
-                buf = b""
-                while CR not in buf:
-                    chunk = s.recv(256)
-                    if not chunk:
-                        break
-                    buf += chunk
-                return buf
+                if expect_reply:
+                    buf = b""
+                    while CR not in buf:
+                        chunk = s.recv(256)
+                        if not chunk:
+                            break
+                        buf += chunk
+                    return buf
+                # 写指令: 短暂等待, 捕获机器拒绝(ERR/!); 超时则视为成功
+                s.settimeout(0.3)
+                try:
+                    buf = b""
+                    while CR not in buf:
+                        chunk = s.recv(256)
+                        if not chunk:
+                            break
+                        buf += chunk
+                except socket.timeout:
+                    buf = b""
+                if buf:
+                    text = buf.rstrip(b"\r\n").decode("latin-1", errors="replace")
+                    if text.startswith("ERR") or text.startswith("!"):
+                        raise CoderError(f"喷码机拒绝指令 {frame!r}: {text}")
+                return b""
+        except CoderError:
+            raise
         except (socket.timeout, OSError) as e:
             raise CoderError(f"喷码通讯失败 {self.ip}:{self.port} - {e}")