Well, break is a signal on serial line which cannot be generated by normal means. I think that's the definition, and I haven't seen (so far) any controller having problem detecting it or misinterpreting it as a framing error. Also true I came from a desktop and server appliance world, micro-controllers are new to me.dwelch67 wrote: ↑Wed Dec 13, 2017 9:21 pmI dont use break much unless absolutely have to, problem is what is the definition for starters, how long does it have to be asserted to define a break? And then does the uart detect it at all, or detect just a framing error? Are you seeing a framing error and if so does the rx buffer have any data with that framing error?
worst case you can wire the pin to a gpio (in addition to the gpio for uart rx) and interrupt or otherwise monitor the state of the pin vs a timer and detect that way...
I would, but how can I reliably set pl011's baud rate? I couldn't find any example which works on my real hw. I can set everything up properly (GPIO mapping, 8N1 characteristics), it's only the baud rate that is not 115200 no matter what I do. The only thing I haven't tried are dts overlays, which I want to avoid if possible as I don't use the Linux kernel.dwelch67 wrote:or just dont use the mini-uart if you want to detect break.
"Nope"? Sorry if I was unclear, that's exactly what I meant I wanted to say detecting break in a framing error handler seems to be a good idea. My thinking was like this:dwelch67 wrote: ↑Tue Dec 19, 2017 7:02 pmNope, just stating that a break is a framing error. uarts are not all built equal (although a lot like/try to clone the 16550). So if there isnt a specific break detect and/or it doesnt work then perhaps a combination of framing error and rx data maybe you can assume break from that. I have not looked at these uarts on this topic so dont know what I would try...
Yes, because M$ acquired github, I've removed my boot loader source. But I've converted everything into a tutorial series, still available on github. The UART0 code is here.
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