On 31/7/25 09:02, jeremy ardley wrote:
On 31/7/25 07:59, mick.crane wrote:
I've never really known what a serial console is.
Say in relation to a Raspberry Pi or Arduino
I assumed a serial console was a device with a screen and keyboard.
When people talk about a serial console they are talking about
connecting a Debian PC to a device with a parallel, wired cable to a
parallel port or an adaptor on a PC and emulating this console thing
with software?
Like a telnet connection?
mick
For the Pi and most SBC devices they are talking about a TTL level
signal that is transmitted in some pins on one of the headers. The
data format is the same as serial RS-232 but at 5V or 3V and a few
signals are supported - Tx, Tx, Gnd, VCC (to power the card)
The card I have also has pins for DTR# RTS# RI# DSR# DCD# CTS# that
you could connect to spare output pins on the Pi to emulate an old
style modem.
You need to buy a cheap (like $5) card that takes the TTL level
signal and converts it to serial USB. You plug the USB into a suitable
host.
FYI The interface card I have is labelled FT232RL and says "USB TO TTL
5V/3.3V/1.8V"
I had to make up a special cable to plug into the SBC header pins and
into the basic serial interface header on the adaptor card
