Further testing with BW16 modules with default/shipped unmodified firmware also exhibit this issue when connecting to nearby open (no password) wifi AP. Using ATPN=xyz at “#” prompt on the LOG UART results in below. Sometimes its a Hard Fault, sometimes the prompt stops reacting with repeating “fw cmd fifo full”, sometimes just reboots. FWIW the AP I am connecting to causes no problems for any other devices (ESP… or otherwise) and is an OpenWRT device. Any help here would be appreciated.
#ATPN=xyz
RTL8721D[Driver]: set ssid [xyz]
RTL8721D[Driver]: start auth to 00:2a:a8:87:b5:3d
RTL8721D[Driver]: auth success, start assoc
RTL8721D[Driver]: association success(res=13)
wlan1: 1 DL RSVD page success! DLBcnCount:01, poll:00000001
Interface 0 IP address : 192.168.19.190
[MEM] After do cmd, available heap 169336
Hard Fault Error!!!
R0 = 0x0
R1 = 0x1
R2 = 0x40080054
R3 = 0xc000002
R12 = 0xc005b61
LR = 0xc005bc1
PC = 0xc000002
xPSR = 0x20000000
PriMask: 0x0
fw cmd fifo full 2
MAC_1C0=00000000, MAC_1C4=00000000, MAC_1C8=00000010, MAC_1CC=0000000f
fw cmd fifo full 2
MAC_1C0=00000000, MAC_1C4=00000000, MAC_1C8=00000010, MAC_1CC=0000000f