# Can't read Modbus TCP 32bit integer as single register

**URL:** <https://forum.inductiveautomation.com/t/cant-read-modbus-tcp-32bit-integer-as-single-register/28733>\
**Category:** Ignition\
**Tags:** ignition80\
**Created:** [October 2, 2019, 11:13am UTC](https://forum.inductiveautomation.com/t/cant-read-modbus-tcp-32bit-integer-as-single-register/28733 "2019-10-02T11:13:51Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![enertec](https://avatars.discourse-cdn.com/v4/letter/e/e9bcb4/32.png) [@enertec](https://forum.inductiveautomation.com/u/enertec)\
**Post date:** [October 2, 2019, 11:13am UTC](https://forum.inductiveautomation.com/t/cant-read-modbus-tcp-32bit-integer-as-single-register/28733/1 "2019-10-02T11:13:51Z")

</div>

Hi  
Ignition 8.0.4 on Ubuntu

There are 3rd party application data we need to access by Modbus TCP -  
this is 32bit integers registers, as you see below

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/2X/7/74e5336efeb81531f8e948412f67f5255f64e6aa.png)

I can read this with Modbus scanner and data is OK (524503)

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/2X/c/c06643a5e273dda6da9ea96a3cfa24666603515c.png)

I try to do the same in Ignition in two ways:

1. Adding tag (one) manually with any combination IRI, IRUI…  
 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/2X/1/1a1ca770452486c6e84e17d39ba9df511ff7deeb.png)

2. Add one tag from Gateway web interface - \> device - \>Adresses  

In both case, Client (i can see its console) recieve requests for two Registers 4096 and 4097 and answer, but Ignition tags cant reach proper value

Please help

---

<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:** [October 2, 2019, 11:36am UTC](https://forum.inductiveautomation.com/t/cant-read-modbus-tcp-32bit-integer-as-single-register/28733/2 "2019-10-02T11:36:52Z")

</div>

Ignition’s Modbus driver doesn’t have any support for these 32-bit registers because they aren’t part of the Modbus spec. The only way to read a 32-bit value with the Ignition driver is to combine two 16-bit registers into a 32-bit value, which is what happens when you select Int32 or UInt32 datatype.

---

<div class="post-metadata">

**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [October 2, 2019, 11:39am UTC](https://forum.inductiveautomation.com/t/cant-read-modbus-tcp-32bit-integer-as-single-register/28733/3 "2019-10-02T11:39:47Z")

</div>

Try changing the driver setting of “Reverse Word Order”, and possibly “One-Based Addressing”. What you show in the modbus scanner doesn’t correspond with the data shown in the Ignition tag browser.

---

<div class="post-metadata">

**Author:** ![enertec](https://avatars.discourse-cdn.com/v4/letter/e/e9bcb4/32.png) [@enertec](https://forum.inductiveautomation.com/u/enertec)\
**Post date:** [October 2, 2019, 2:30pm UTC](https://forum.inductiveautomation.com/t/cant-read-modbus-tcp-32bit-integer-as-single-register/28733/4 "2019-10-02T14:30:06Z")

</div>

This options don’t help