
#USING MINICOM SERIAL#
But maybe you don't have a USB serial adapter handy, but do have a spare (second) Raspberry Pi. Update: I also forgot to mention-it's possible to get output from the Pi's own bootloader (at an even earlier stage) using the BOOT_UART option supplied to a custom EEPROM build see cleverca22's post in the Pi Forums for details. I've done this process a few times in the past, but I've grown tired of looking back at old notes to remember specifically which pins to use on the GPIO, since I don't do it that often and the pins are unlabeled on most Pis. See also: Adafruit's guide to using a serial console on the Pi. Note: To exit the screen session, press Ctrl-A, then Ctrl-K, and confirm you want to exit. Note: In metacom, the Meta key is mapped to 'Esc' by default, at least on macOS. Within a few seconds, you should see data in your session.
#USING MINICOM INSTALL#
#USING MINICOM MAC#
There are a number of ways to interact with the serial console on a Mac (and most are the same as on Linux, with sometimes minor usage differences), but the two I've used in the past are minicom and screen. That's the device you'll connect to on your Mac.

If you want to access the Pi's serial console, here's what you need to do: Simply Embedded has a great overview of UART if you want to learn more. Many devices-including things like storage controller cards, which in a sense run their own internal operating system on an SoC-have a 'UART header', which is typically three or four pins that can connect over the RS-232 standard (though many do not operate at 12v like a traditional serial port! Use a USB-to-TTL adapter like the one I mention below). The Raspberry Pi can output information over a 'serial console', technically known as a UART (Universal Asynchronous Receiver/Transmitter). Or maybe you're like me, and someone 'accidentally' cut your Raspberry Pi in half, and you want to see what it's doing since it won't boot anymore. Or you don't have an HDMI display, and you can't log into your Pi via SSH. Or it'll boot, but it'll do weird things.
