# Referring to current parameterNumber in sysex data

**URL:** <https://forum.electra.one/t/referring-to-current-parameternumber-in-sysex-data/771>\
**Category:** Developers\
**Created:** [June 7, 2021, 3:47am UTC](https://forum.electra.one/t/referring-to-current-parameternumber-in-sysex-data/771 "2021-06-07T03:47:35Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![shankar](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.electra.one/shankar/32/463_2.png) [@shankar](https://forum.electra.one/u/shankar)\
**Post date:** [June 7, 2021, 3:47am UTC](https://forum.electra.one/t/referring-to-current-parameternumber-in-sysex-data/771/1 "2021-06-07T03:47:35Z")

</div>

My preset for Triton has a bunch of controls with negative values as I had mentioned in [an earlier thread](https://forum.electra.one/t/twos-complement-question-issue-solved/605). When I send parameter change for these, I need to split the negative value and send it in two bytes like below:

```auto
[
  "42",
  {
    "type": "value",
    "rules": [
      {
        "parameterNumber": 1
      }
    ]
  },
  "50",
  "41",
  "03",
  "00",
  "2A",
  "00",
  "03",
  {
    "type": "value",
    "rules": [
      {
        "parameterNumber": 353,
        "parameterBitPosition": 7,
        "byteBitPosition": 0,
        "bitWidth": 1
      }
    ]
  },
  {
    "type": "value",
    "rules": [
      {
        "parameterNumber": 353,
        "parameterBitPosition": 0,
        "byteBitPosition": 0,
        "bitWidth": 7
      }
    ]
  }
]

```

Here, 353 is the current parameter number. While this works fine, it is a lot of manual effort to refer to the right parameter number in each sysex data (I have dozens of these). It would be super cool if there is a way to refer to the current parameter number or just leave it blank for the system to understand I am referring to the current parameter number (latter preferable, of course). That way, I just need to copy paste the same JSON on each control that supports negative values.

Alternatively, if I can do this in Lua, that’s awesome too 🙂.