# \[SOLVED\] Unable to use system.tag.writeAsync in the script console

**URL:** <https://forum.inductiveautomation.com/t/solved-unable-to-use-system-tag-writeasync-in-the-script-console/38492>\
**Category:** Ignition\
**Tags:** vision, ignition80\
**Created:** [September 8, 2020, 8:03pm UTC](https://forum.inductiveautomation.com/t/solved-unable-to-use-system-tag-writeasync-in-the-script-console/38492 "2020-09-08T20:03:18Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![bmeyers](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bmeyers/32/37453_2.png) [@bmeyers](https://forum.inductiveautomation.com/u/bmeyers)\
**Post date:** [September 8, 2020, 8:03pm UTC](https://forum.inductiveautomation.com/t/solved-unable-to-use-system-tag-writeasync-in-the-script-console/38492/1 "2020-09-08T20:03:18Z")

</div>

Good afternoon,

I am unable to run the following code in the Script Console. Anyone know what I’m doing wrong?

```
def callBack(arr):
    pass

path = "[MEPS]MerLine/General/del"
value = 108
system.tag.writeAsync(path, value, callBack)

```

Gives me the following error.

```
Java Traceback:
Traceback (most recent call last):
File "<input>", line 6, in <module>
at com.inductiveautomation.ignition.common.TypeUtilities.coerce(TypeUtilities.java:1417)

at com.inductiveautomation.ignition.common.script.builtin.PyArgumentMap.coerce(PyArgumentMap.java:125)

at com.inductiveautomation.ignition.common.script.builtin.PyArgumentMap.interpretPyArgs(PyArgumentMap.java:81)

at com.inductiveautomation.ignition.common.script.builtin.PyArgumentMap.interpretPyArgs(PyArgumentMap.java:39)

at com.inductiveautomation.ignition.common.script.builtin.AbstractTagUtilities.writeAsync(AbstractTagUtilities.java:368)

at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)

at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

at java.base/java.lang.reflect.Method.invoke(Unknown Source)

java.lang.ClassCastException: java.lang.ClassCastException: Cannot coerce value 
'[MEPS]MerLine/General/del' into type: interface java.util.List

at org.python.core.Py.JavaError(Py.java:552)

at org.python.core.Py.JavaError(Py.java:543)

at org.python.core.PyReflectedFunction. __call__ (PyReflectedFunction.java:190)

at com.inductiveautomation.ignition.common.script.ScriptManager$ReflectedInstanceFunction. __call__ (ScriptManager.java:524)

at org.python.core.PyObject. __call__ (PyObject.java:515)

at org.python.core.PyObject. __call__ (PyObject.java:519)

at org.python.pycode._pyx12.f$0(<input>:6)

at org.python.pycode._pyx12.call_function(<input>)

at org.python.core.PyTableCode.call(PyTableCode.java:171)

at org.python.core.PyCode.call(PyCode.java:18)

at org.python.core.Py.runCode(Py.java:1614)

at org.python.core.Py.exec(Py.java:1658)

at org.python.util.PythonInterpreter.exec(PythonInterpreter.java:276)

at org.python.util.InteractiveInterpreter.runcode(InteractiveInterpreter.java:131)

at com.inductiveautomation.ignition.designer.gui.tools.jythonconsole.JythonConsole$ConsoleWorker.doInBackground(JythonConsole.java:605)

at com.inductiveautomation.ignition.designer.gui.tools.jythonconsole.JythonConsole$ConsoleWorker.doInBackground(JythonConsole.java:593)

at java.desktop/javax.swing.SwingWorker$1.call(Unknown Source)

at java.base/java.util.concurrent.FutureTask.run(Unknown Source)

at java.desktop/javax.swing.SwingWorker.run(Unknown Source)

at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)

at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)

at java.base/java.lang.Thread.run(Unknown Source)

Caused by: java.lang.ClassCastException: Cannot coerce value '[MEPS]MerLine/General/del' into type: interface java.util.List

at com.inductiveautomation.ignition.common.TypeUtilities.coerce(TypeUtilities.java:1417)

at com.inductiveautomation.ignition.common.script.builtin.PyArgumentMap.coerce(PyArgumentMap.java:125)

at com.inductiveautomation.ignition.common.script.builtin.PyArgumentMap.interpretPyArgs(PyArgumentMap.java:81)

at com.inductiveautomation.ignition.common.script.builtin.PyArgumentMap.interpretPyArgs(PyArgumentMap.java:39)

at com.inductiveautomation.ignition.common.script.builtin.AbstractTagUtilities.writeAsync(AbstractTagUtilities.java:368)

at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)

at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

at java.base/java.lang.reflect.Method.invoke(Unknown Source)

at org.python.core.PyReflectedFunction. __call__ (PyReflectedFunction.java:188)

... 19 more

Traceback (most recent call last):
  File "<input>", line 6, in <module>
at com.inductiveautomation.ignition.common.TypeUtilities.coerce(TypeUtilities.java:1417)

at com.inductiveautomation.ignition.common.script.builtin.PyArgumentMap.coerce(PyArgumentMap.java:125)

at com.inductiveautomation.ignition.common.script.builtin.PyArgumentMap.interpretPyArgs(PyArgumentMap.java:81)

at com.inductiveautomation.ignition.common.script.builtin.PyArgumentMap.interpretPyArgs(PyArgumentMap.java:39)

at com.inductiveautomation.ignition.common.script.builtin.AbstractTagUtilities.writeAsync(AbstractTagUtilities.java:368)

at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)

at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

at java.base/java.lang.reflect.Method.invoke(Unknown Source)

java.lang.ClassCastException: java.lang.ClassCastException: Cannot coerce value '[MEPS]MerLine/General/del' into type: interface java.util.List
```

---

<div class="post-metadata">

**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [September 8, 2020, 8:04pm UTC](https://forum.inductiveautomation.com/t/solved-unable-to-use-system-tag-writeasync-in-the-script-console/38492/2 "2020-09-08T20:04:12Z")

</div>

`writeAsync` expects a list of paths and values.

Try this instead:

```auto
system.tag.writeAsync([path], [value], callBack)

```

---

<div class="post-metadata">

**Author:** ![bmeyers](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bmeyers/32/37453_2.png) [@bmeyers](https://forum.inductiveautomation.com/u/bmeyers)\
**Post date:** [September 8, 2020, 8:05pm UTC](https://forum.inductiveautomation.com/t/solved-unable-to-use-system-tag-writeasync-in-the-script-console/38492/3 "2020-09-08T20:05:21Z")

</div>

Thanks, I was looking at this way too long.