Chapter 4. Software framework
• Earlier IDF versions do not have the above options, so please refer to lwipopts.h line 806 and 807, to change
LWIP_DBG_OFF to LWIP_DBG_ON in both lines of code as follows.
#define DHCP_DEBUG LWIP_DBG_ON
#define LWIP_DEBUG LWIP_DBG_ON
4.10.103 When ESP32 works as a softAP, the station connected to it does not get the IP.
How to debug?
To open the debug log of DHCP in lwIP for debugging, please go to dhcpserver.c and change #define
DHCPS_DEBUG 0 to #define DHCPS_DEBUG 1.
4.10.104 In ESP-IDF menucong, after Component config > PHY > Max Wi-Fi
TX power(dBm)
is congured to adjust the Wi-Fi transmit power, what is the
actual power? For example, what is the actual maximum transmit power when
the option is congured to 17 dBm?
• For ESP32, the actual maximum transmit power in the example is 16 dBm. For the mapping rules, please refer
to the function esp_wi_set_max_tx_power().
• For ESP32-C3, the maximum transmit power value congured in menucong is the actual maximum power
value.
4.10.105 ESP-IDF currently supports connecting to Chinese SSID routers with UTF-8
encoding. Is there a way to connect to Chinese SSID routers with GB2312 en-
coding?
Yes, please keep the encoding method of the ESP device consistent with that of the router. In this case,
make the ESP device also use the GB2312-based Chinese SSID.
4.10.106 After connecting to the router, ESP32 consumes much power in an idle state,
with an average current of about 60 mA. How to troubleshoot the issue?
• Please capture Wi-Fi packets for further analysis. See espressif Wireshark User Guide. After the packets are
captured, check whether the NULL data packet sent by the device contains NULL(1). If NULL(1) is sent
every 10 seconds, it means that ESP32 is interacting with the router in keepalive mode.
• You can also check the TIM(Traffic Indication Map) eld of the beacon packet in the captured
packets. If Traffic Indication is equal to 1, it means Group Frames Buered. In this case, ESP32
will turn on RF, resulting in higher power consumption.
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