And here is that instruction for:
Activating the DRAWS? on HamPi requires a few simple changes. The first is modifying the
/boot/config.txt file, this can be done after you burn the image to the SD either while still mounted to
your computer where you copied the image, or by editing with your preferred editor, such as nano or
vi, after the HamPi image is booted.
Example using vi (sudo should be used with the editor to overcome permissions issues):
sudo vi /boot/config.txt
Near the bottom of the file you must uncomment the highlighted lines:
# Flush all overlays, ie. deprecated overlays loaded from eeprom
dtoverlay=
# Enable UDRC/DRAWS if no EEPROM
dtoverlay=draws,alsaname=udrc
# https://www.raspberrypi.org/documentation/configuration/configtxt/overclocking.md
force_turbo=1
Save the file and reboot.
See that these new device files now appear:
pi@hampi:~ $ cd /dev && ls -l ttySC0 ttySC1 pps0
crw-rw---- 1 root root 241, 0 Jun 8 17:46 pps0
crw-rw---- 1 root dialout 239, 0 Jun 8 17:46 ttySC0
crw-rw---- 1 root dialout 239, 1 Jun 8 17:46 ttySC1?
As you'll notice - I get totally something else as result
