@NickBoots , If you are connecting to an Access point from your pycom device (i.e Wifi in STA mode) disable the wifi on boot option via this command pycom.wifi_on_boot(False) reset board and try again.
Found the issue. It was actually caused by gc.collect() run time going from 6mS to 48mS. This was being run inside a timer tic ISR (I know, that's a no-no). The ISR was taking longer to run than the timer tic period. I assume the UART Int is a lower priority than the timer so it was never being processed.
Is gc.collect() taking so long because of the extra memory or is this a bug?
@robert-hh Number of concurrent transfers didn't make any difference. But the command line seem to work, and more importantly for me, it works from python with ftplib.
I'll just stop using filezilla...
@robert-hh Yes, it's important what Robert writes! The kind of connection--and IP(!!)--is related to the network the WiPy is connected. In case the WiPy is started default it will start as access point. In this case the IP is 192.168.1.1 In case you have connected the WiPy to a home network and the WiPy is now a station and not an access point any more, the device gets the IP from the network. I had a look at my Fritz box dashboard and could so figure out the IP but I think you can also gather the IP via a serial connection?