# Runtime error: DMA channel not started on Ultra96

**URL:** <https://discuss.pynq.io/t/runtime-error-dma-channel-not-started-on-ultra96/8021>\
**Category:** Support\
**Created:** [February 6, 2025, 8:45am UTC](https://discuss.pynq.io/t/runtime-error-dma-channel-not-started-on-ultra96/8021 "2025-02-06T08:45:42Z")\
**Posts on this page:** 1\
**Showing post:** 3

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**Author:** ![marioruiz](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/marioruiz/32/2177_2.png) [@marioruiz](https://discuss.pynq.io/u/marioruiz)\
**Post date:** [February 6, 2025, 1:10pm UTC](https://discuss.pynq.io/t/runtime-error-dma-channel-not-started-on-ultra96/8021/3 "2025-02-06T13:10:52Z")

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Hi @cool,

Welcome to the PYNQ community.

This is likely due to TLAST and input and output buffer size. I wrote extensible about debugging this. [Debugging Common DMA Issues [Part 3]](https://discuss.pynq.io/t/debugging-common-dma-issues-part-3/7157)

Mario

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