During startup the nRF sniffer extcap script does the following:
def find_sniffer(write_data=False):
open_ports = list_ports.comports()
sniffers = []
for port in [x.device for x in open_ports]:
for rate in SNIFFER_BAUDRATES:
reader = None
try:
reader = Packet.PacketReader(portnum=port, baudrate=rate)
try:
if write_data:
reader.sendPingReq()
_ = reader.decodeFromSLIP(0.1, complete_timeout=0.1)
else:
_ = reader.decodeFromSLIP(0.3, complete_timeout=0.3)
# FIXME: Should add the baud rate here, but that will be a breaking change
sniffers.append(port.encode('ascii', 'ignore'))
break
except (Exceptions.SnifferTimeout, Exceptions.UARTPacketError):
pass
except (serial.SerialException, ValueError):
continue
finally:
if reader is not None:
reader.doExit()
return sniffers
Which (at least on Linux) breaks applications having open serial ports.
Why not instead use serial.tools.list_ports.comports(? Something like this:
for port in serial.tools.list_ports.comports():
if "J-Link - CDC" in port.description:
return port.device
