# Help in understanding output from Modbus node

**URL:** <https://discourse.nodered.org/t/help-in-understanding-output-from-modbus-node/28194>\
**Category:** General\
**Created:** [11 June 2020 18:34 UTC](https://discourse.nodered.org/t/help-in-understanding-output-from-modbus-node/28194 "2020-06-11T18:34:43Z")\
**Posts on this page:** 1\
**Showing post:** 5

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**Author:** ![grant1](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/grant1/32/49890_2.png) [@grant1](https://discourse.nodered.org/u/grant1)\
**Post date:** [11 June 2020 23:17 UTC](https://discourse.nodered.org/t/help-in-understanding-output-from-modbus-node/28194/5 "2020-06-11T23:17:20Z")

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Thank you Steve. That node does the trick nicely. In fact, I am trying to read quite a few registers (not just registers 121 and 122). So I figured I could change the code in your Node to add register 123, for example:  
 ![Node JS integer conversion](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/6/d/6d7798d0e23a009502c415a6697ad97729662655.jpeg)  
but it does not work (gives me _SyntaxError: Unexpected token { in JSON at position 351_ and when I go back to the node editor, it lost the formatting, i.e. looks like this _{ "options": { "resultType": "object", "singleResult": true }, "items": [ {_

so I have obviously wandered above my knowledge grade. I can still make it work with the array[2] node you provided.

The real end game is to get a whole slew of values from the device (shown in bold below), which I believe will be possible with your node if I can get the syntax correct.  
**|122|Probe Sensor mV value**  
**|123|Process Variable**  
**|124|Dew point value**  
**|125|Probe Temperature**  
**|126|CO measured value**  
|127|Probe Resistance value  
|128|Probe Response Time  
|129|Probe Temperature at last Probe Test  
|130|Main Control Output Value  
|131|Secondary Control Output Value  
|132|PID Out Value - % Output|  
|133|Main Control Ouput Display value  
|134|Secondary Control Output Display Value  
|135|Device Status Mode  
|136|Type of Operative setpoint  
**|137|Operative Setpoint value**  
|138|Remote Setpoint value  
|139|Not Used  
|140|Not Used  
|141|Not Used  
**|142|CO Factor**  
**|143|H2 Factor**  
**|144|%O2 process variable**

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