I've bought a Raspberry Pi 3 model b and a new design of Berryclip which is supposed to include the USB to serial adapter as an additional microUSB port for the Raspberry. Now I've been told that the power still has to come from the usual microUSB port.
Here are the instructions for the typical serial connector which are supposed to be the same as the instructions for the one I have:
The first thing we have to do is load the bootloader https://github.com/dwelch67/raspberrypi/blob/master/bootloader05/kernel.img?raw=true in the SD and feed the Raspberry. It is necessary to reset the Raspberry every time we want to load a new Bare Metal program, and this is done manually by unplugging and plugging in the power, or with the automatic method that we explained in the last section. We must connect the 3 cables that go from the USB-serial adapter to the Raspberry, with the third, fourth and fifth pins of the upper row of the GPIO port. The third pin is the ground, in the adapter is a black wire or marked with GND in the screen. The fourth pin is GPIO 14 or TXD, which corresponds to the RXD pin on the adapter. Finally the fifth pin is GPIO 15 or RXD and it is connected to pin TXD of the adapter. Note that the cables are crossed, the pin that transmits from the PC is the one that receives in the Raspberry and vice versa.
I haven't done anything with the kernel image as I have already flashed raspbian in the sdcard and besides I don't know what to do with that image.
I've also added the line
enable_uart=1 to the file
/boot/config.txt of the raspberry.
Then I've looked some tutorials (RPi Serial Connection,
Connect to the Raspberry PI Serial Port from a Linux PC that explain what I'm asking now but they assume the name of the device path is
/dev/ttyUSB0. I don't have that device path at this point, with the power microUSB connected to a plug and the other to my PC. Like this:
So I have to find the name for the device path of the USB port connected to the Raspberry. I've looked other tutorials (Serial HOWTO, How to find which serial port is in use). But in my PC I don't get anything with that command:
dmesg | grep tyyS
Unless I connect the power microUSB to the computer:
dmesg | grep ttyS [12741.466227] usb 2-1: ch341-uart converter now attached to ttyUSB0
I get an error when I run
❯ sudo screen /dev/ttyUSB0 115200 Cannot exec `/dev/ttyUSB0`: No such file or directory