Data logging does not work

[laurensvalk]

A program such as one of the following used to produce local text files on the host, but this no longer works in the new protocol.

# Output between the begin/end commands will be saved to "control.txt".
print("_file_begin_", "control.txt")
print("57,56,2,0,2,32000,4,84,4,88,50000,0,-18000,1073898496")
print("62,61,2,0,2,54500,4,91,4,90,50000,0,4500,65")
print("67,66,2,0,2,48000,5,100,5,106,75000,0,-27000,65")
print("72,71,2,0,2,48000,5,100,5,106,75000,0,-27000,65")
print("_file_end_")

from pybricks.pupdevices import Motor
from pybricks.tools import wait
from pybricks.parameters import Port
from pybricks import version

print(version)

# Initialize the motor.
motor = Motor(Port.A)

# Allocate the data logs.
DURATION = 4000
motor.log.start(DURATION)
motor.control.log.start(DURATION)

# Run the motor.
motor.run_target(500, 360)

# Wait so we can also log the stopped behavior.
wait(500)
motor.stop()

# Transfer data logs.
print("Transferring data...")
motor.log.save("servo.txt")
motor.control.log.save("control.txt")
print("Done")

[laurensvalk]

We could restore it in the near term, but maybe we can brainstorm a better/generic method to create and save data on the host.

Since Pybricks Code supports files too now, maybe we could allow the user to create files on the host.

host_file = open("HOST/data.txt", "w")

print("1, 2, 3", file=host_file)  # Labels the data in such a way that the IDE knows it goes into file, not standard output.