# Standard data type inside a custom one

**URL:** <https://forum.opencyphal.org/t/standard-data-type-inside-a-custom-one/960>\
**Category:** Applications & Usage\
**Created:** [October 18, 2020, 10:36am UTC](https://forum.opencyphal.org/t/standard-data-type-inside-a-custom-one/960 "2020-10-18T10:36:24Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![semiliranda](https://forum.opencyphal.org/user_avatar/forum.opencyphal.org/semiliranda/32/698_2.png) [@semiliranda](https://forum.opencyphal.org/u/semiliranda)\
**Post date:** [October 18, 2020, 10:36am UTC](https://forum.opencyphal.org/t/standard-data-type-inside-a-custom-one/960/1 "2020-10-18T10:36:24Z")

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I use two standard data types inside my custom data type.

```auto
SynchronizedTimestamp.1.0[<=32767] timestamp
uint16[<=32767] sensor
Real32.1.0[<=32767] value

```

These two standard data type definitions are located in the same directory, as the custom one (_a/b/custom_). Here ist the error message I get on compilation

> uavcan.dsdl.common.DsdlException: a/b/custom/MyType.0.1.uavcan:5: Unknown namespace [SynchronizedTimestamp.1]  
> Compiler failure

How can I fix it?

---

<div class="post-metadata">

**Author:** ![pavel.kirienko](https://forum.opencyphal.org/user_avatar/forum.opencyphal.org/pavel.kirienko/32/9_2.png) [@pavel.kirienko](https://forum.opencyphal.org/u/pavel.kirienko)\
**Post date:** [October 18, 2020, 10:39am UTC](https://forum.opencyphal.org/t/standard-data-type-inside-a-custom-one/960/2 "2020-10-18T10:39:25Z")

</div>

It seems like you are trying to use v0 compiler against v1 data types. You can’t do that; please use the v1 code generator (Nunavut/PyUAVCAN, depending on your needs).