# How to write to multiple registers using FC 16

**URL:** <https://discourse.nodered.org/t/how-to-write-to-multiple-registers-using-fc-16/41609>\
**Category:** General\
**Created:** [25 February 2021 08:46 UTC](https://discourse.nodered.org/t/how-to-write-to-multiple-registers-using-fc-16/41609 "2021-02-25T08:46:27Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Waled22](https://avatars.discourse-cdn.com/v4/letter/w/13edae/32.png) [@Waled22](https://discourse.nodered.org/u/Waled22)\
**Post date:** [25 February 2021 08:46 UTC](https://discourse.nodered.org/t/how-to-write-to-multiple-registers-using-fc-16/41609/1 "2021-02-25T08:46:27Z")

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Hi there,  
I want to write these Modbus registers (attached figure), however, I am getting confused about what to write in function code while using FC 16. I am able to write them individually using FC 06, individual function nodes, and Modbus Flex Write, but I don't know how to use FC 16 and single function node for this purpose. Thanks in advance.  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/4/d4bb28ceecedfae41cd832f0815a5a1ed1191790.png)

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<div class="post-metadata">

**Author:** ![UnborN](https://avatars.discourse-cdn.com/v4/letter/u/4491bb/32.png) [@UnborN](https://discourse.nodered.org/u/UnborN)\
**Post date:** [25 February 2021 10:23 UTC](https://discourse.nodered.org/t/how-to-write-to-multiple-registers-using-fc-16/41609/2 "2021-02-25T10:23:27Z")

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Hi Waled

try sending an array of your values

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/2/3/232d03a80a3e3a22359dab134312e3566707368f.png)

**Example Flow (change the id,starting address and Config to match your device) :**

```auto
[{"id":"efa9728f.a7be6","type":"modbus-flex-write","z":"981a2a72.4329f","name":"","showStatusActivities":false,"showErrors":false,"server":"bf37180a.2d18e","emptyMsgOnFail":false,"keepMsgProperties":false,"x":610,"y":1000,"wires":[["f373a2e5.227c68"],[]]},{"id":"cb5984b6.2e3d5","type":"function","z":"981a2a72.4329f","name":"FC16","func":"msg.payload = { \n \n 'value': msg.payload,\n 'fc': 16,\n 'unitid': 1,\n 'address': 0,\n 'quantity': 4\n \n} \nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","x":410,"y":1000,"wires":[["efa9728f.a7be6"]]},{"id":"2e320cc4.ec9aec","type":"inject","z":"981a2a72.4329f","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"[11,22,33,44]","payloadType":"json","x":230,"y":1000,"wires":[["cb5984b6.2e3d5"]]},{"id":"f373a2e5.227c68","type":"debug","z":"981a2a72.4329f","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":830,"y":960,"wires":[]},{"id":"bf37180a.2d18e","type":"modbus-client","name":"","clienttype":"tcp","bufferCommands":true,"stateLogEnabled":false,"queueLogEnabled":false,"tcpHost":"192.168.1.66","tcpPort":"502","tcpType":"DEFAULT","serialPort":"/dev/ttyUSB","serialType":"RTU-BUFFERD","serialBaudrate":"9600","serialDatabits":"8","serialStopbits":"1","serialParity":"none","serialConnectionDelay":"100","unit_id":1,"commandDelay":20,"clientTimeout":1000,"reconnectOnTimeout":true,"reconnectTimeout":2000,"parallelUnitIdsAllowed":true}]

```

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [26 April 2021 10:24 UTC](https://discourse.nodered.org/t/how-to-write-to-multiple-registers-using-fc-16/41609/3 "2021-04-26T10:24:16Z")

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