# Custom IP generates different results and DMA stuck at 'dma.recvchannel.wait()'

**URL:** https://discuss.pynq.io/t/custom-ip-generates-different-results-and-dma-stuck-at-dma-recvchannel-wait/8013
**Category:** Support
**Created:** [February 5, 2025, 4:41pm UTC](https://discuss.pynq.io/t/custom-ip-generates-different-results-and-dma-stuck-at-dma-recvchannel-wait/8013 "2025-02-05T16:41:00Z")
**Posts on this page:** 1
**Showing post:** 2

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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 5, 2025, 7:08pm UTC](https://discuss.pynq.io/t/custom-ip-generates-different-results-and-dma-stuck-at-dma-recvchannel-wait/8013/2 "2025-02-05T19:08:59Z")

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Hi @atb,

Welcome to the PYNQ community.

Based on your description, the IP is not setting up TLAST properly. I wrote a comprehensive tutorial to debug this on board. [Debugging Common DMA Issues [Part 3]](https://discuss.pynq.io/t/debugging-common-dma-issues-part-3/7157)

> - My custom IP generates different results (with the same input data) every time I run it on hardware using PYNQ’ .

If the DMA is not finishing correctly, it is likely that the data you’re reading is not correct. You should fix the DMA issue first before debugging this.

Mario

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