any easy solution to get monitor_port value from platformio.ini file?
If the value is explicitly set in the platformio.ini one can do
Import("env")
print("Monitor port is %s " % env.GetProjectOption("monitor_port"))
Of that option is not set it will be empty.
If the monitor port is is identical to the upload port one can do
Import("env")
from platformio.builder.tools.pioupload import AutodetectUploadPort
AutodetectUploadPort(env)
print("Port is %s " % env.subst("$UPLOAD_PORT"))
Otherwise one would have to do the same logic that the pio device monitor command does to figure out the monitor port
Here’s a minimal way with the original pio monitor logic
Import("env")
from platformio.commands.device import helpers as device_helpers
from platformio import exception, fs, util
platform = env.PioPlatform()
#print(platform)
project_options = device_helpers.get_project_options(env["PIOENV"])
#print(project_options)
kwargs = {}
monitor_port = ""
if "monitor_port" in project_options:
# use predefined value
monitor_port = project_options["monitor_port"]
else: # search
ports = util.get_serial_ports(filter_hwid=True)
if len(ports) == 1:
kwargs["port"] = ports[0]["port"]
monitor_port = kwargs["port"]
elif "platform" in project_options and "board" in project_options:
board_hwids = device_helpers.get_board_hwids(
kwargs["project_dir"],
platform,
project_options["board"],
)
for item in ports:
for hwid in board_hwids:
hwid_str = ("%s:%s" % (hwid[0], hwid[1])).replace("0x", "")
if hwid_str in item["hwid"]:
kwargs["port"] = item["port"]
break
if kwargs["port"]:
break
# contains "port" entry
#print(kwargs)
monitor_port = kwargs["port"]
print("Final monitor port: %s" % monitor_port)
if I use that as extra script while having no monitor_port option set, I get the automatic upload port, and if I have monitor_port set, it gives me that. Works in both cases.
Thanks Max !!!
env.GetProjectOption(“monitor_port”) work fine
But if it’s not set it in the platformio.ini it won’t work 
no problems 
I need this to reset Pico to boot-uf2 if is used USB stdio ( without button and cable )
@maxgerhardt, I wonder about this part in your example
monitor_port = project_options[“monitor_port”]
In the general case, the value of ‘monitor_port’ is defined as a regex (glob), not as a port name, right? Will that code work correctly for example if monitor_port = COM[234]?
https://docs.platformio.org/en/latest/projectconf/section_env_monitor.html#monitor-port
If it’s indeed a glob expression, how would you go for determining the port under Windows?
(Found this thread due to a problem I just encountered with the U2F loader which uses the port to force the Pico into BOOT mode, no intention to nit pick old posts ;-))
Yes, in case of a GLOB expresionn, additional logic is missing, see