Detailed description
In this PR we address the issues encountered by the aux serial engine if the UARTs on the v3 are swapped back and forth between repeatedly. The main cause of this boils down to the number-of-data value getting progressively out of sync with the actual size of the FIFO and resulting in incredibly bugged out behaviour, up to and including a full crash of the data moving process for receive.
Your checklist for this pull request
- I've read the Code of Conduct
- I've read the guidelines for contributing to this repository
- It builds for hardware native (see Building the firmware)
- It builds as BMDA (see Building the BMDA)
- I've tested it to the best of my ability
- My commit messages provide a useful short description of what the commits do
Closing issues
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## Detailed description
In this PR we address the issues encountered by the aux serial engine if the UARTs on the v3 are swapped back and forth between repeatedly. The main cause of this boils down to the number-of-data value getting progressively out of sync with the actual size of the FIFO and resulting in incredibly bugged out behaviour, up to and including a full crash of the data moving process for receive.
## Your checklist for this pull request
* [x] I've read the [Code of Conduct](https://codeberg.org/blackmagic-debug/blackmagic/src/CODE_OF_CONDUCT.md)
* [x] I've read the [guidelines for contributing](https://codeberg.org/blackmagic-debug/blackmagic/src/CONTRIBUTING.md) to this repository
* [x] It builds for hardware native (see [Building the firmware](https://codeberg.org/blackmagic-debug/blackmagic?tab=readme-ov-file#building-the-firmware))
* [x] It builds as BMDA (see [Building the BMDA](https://codeberg.org/blackmagic-debug/blackmagic?tab=readme-ov-file#building-black-magic-debug-app))
* [x] I've tested it to the best of my ability
* [x] My commit messages provide a useful short description of what the commits do
## Closing issues
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