Graham Sutherland / Polynomial@ryanc if it does have JTAG somewhere and you can find it and identify the pinout, you'll want a knock-off Segger J-Link. cheap one off eBay or AliExpress, don't bother paying them for the real deal, the cheapo ones work identically. I've seen them for less than £20.
whatever you do, don't bother with OpenOCD's BusPirate JTAG thing, it's literally never worked, you'll spend hours and get nowhere, they really need to pull it from the project.
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