At Thu, 8 Feb 2024 16:10:09 -0800, Steve Rikli <sr%genyosha.net@localhost> wrote: Subject: Re: serial console device, and installboot vs. /boot.cfg > > What constitutes a "fail" for the COM port? Iirc the man page said > "outputs a character" to each COM port, and if it succeeds then that's > the console; else it goes to the PC keyboard for console. Well if there is a (UART) device, and if the device functions to output a character, then it works, even if the char goes blind into the ether! :-) I've always assumed myself that if the port was well-wired to a DCE device that was _not_ asserting DCD (and/or DSR, and CTS) then the output would fail and the code would move on to try the next device. If I remember my RS232 right this should be the case for a disconnected RS232 line, but.... In any case I've never actually tested this with a connected line and a "down" DCE port -- it all might depend on just how the boot code configures the UART, and it may be too lenient and assuming the control lines are irrelevant, which is actually the wrong thing to do in the case where you want to test for a "connected" line. -- Greg A. Woods <gwoods%acm.org@localhost> Kelowna, BC +1 250 762-7675 RoboHack <woods%robohack.ca@localhost> Planix, Inc. <woods%planix.com@localhost> Avoncote Farms <woods%avoncote.ca@localhost>
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