I hope you have a voltmeter. If you do this (see below), you can programmatically set the tx pin (pin 8) of the pi to '1' (3V3) or '0' (0V).
If you don't measure these voltages, it might be your pizero has a broken output - this might happen when you tie them the wrong way with the arduino. Fingers crossed.
If you do measure the voltages, give us the readings on all 6 pins of the leveler.
In the schematic I can see the common ground between the pi (6) and the arduino, but I cannot see it in the picture. You sure it is in place?
If you don't measure these voltages, it might be your pizero has a broken output - this might happen when you tie them the wrong way with the arduino. Fingers crossed.
Code:
pi@openplotter:~ $ ssh tc@10.10.10.3
( '>')
/) TC (\ Core is distributed with ABSOLUTELY NO WARRANTY.
(/-_--_-\) www.tinycorelinux.net
tc@box:~$ sudo sv stop pypilot
ok: down: pypilot: 86313s
tc@box:~$ sudo gpio -g mode 14 output
tc@box:~$ sudo gpio -g write 14 1
tc@box:~$ sudo gpio -g write 14 0If you do measure the voltages, give us the readings on all 6 pins of the leveler.
In the schematic I can see the common ground between the pi (6) and the arduino, but I cannot see it in the picture. You sure it is in place?