# How to use modbusTcp control ur5 by ur5 as modbustcp server? **URL:** \ **Category:** Technical Questions\ **Created:** [June 20, 2022, 3:42am UTC](https://forum.universal-robots.com/t/how-to-use-modbustcp-control-ur5-by-ur5-as-modbustcp-server/22078 "2022-06-20T03:42:07Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![anon48710505](https://avatars.discourse-cdn.com/v4/letter/a/ea666f/32.png) [@anon48710505](https://forum.universal-robots.com/u/anon48710505)\ **Post date:** [June 20, 2022, 3:42am UTC](https://forum.universal-robots.com/t/how-to-use-modbustcp-control-ur5-by-ur5-as-modbustcp-server/22078/1 "2022-06-20T03:42:07Z")
now,I want to use modbus tcp control ur5,I can use [modbus\_read\_registers] read some information by ur5. but when i use [modbus\_write\_registers] control ur5 ,[modbus\_write\_registers] return -1,so I want to know how to use modbusTcp control ur5 by ur5 as modbustcp server? thanyou everybody! ---
**Author:** ![mmi](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.universal-robots.com/mmi/32/691_2.png) [@mmi](https://forum.universal-robots.com/u/mmi)\ **Post date:** [June 20, 2022, 8:28am UTC](https://forum.universal-robots.com/t/how-to-use-modbustcp-control-ur5-by-ur5-as-modbustcp-server/22078/2 "2022-06-20T08:28:03Z")
Take a look at [Modbus Server - 16377 | Universal Robots Support](https://www.universal-robots.com/articles/ur/interface-communication/modbus-server/) TLDR: 16bit registers in range 128-255 can be used to exchange data. ---
**Author:** ![anon48710505](https://avatars.discourse-cdn.com/v4/letter/a/ea666f/32.png) [@anon48710505](https://forum.universal-robots.com/u/anon48710505)\ **Post date:** [June 21, 2022, 1:57am UTC](https://forum.universal-robots.com/t/how-to-use-modbustcp-control-ur5-by-ur5-as-modbustcp-server/22078/3 "2022-06-21T01:57:14Z")
thanyou I will try this