Memory optimization: iram can be used as memory, thus saving about 17KB memory for user application.
Update AT's version to 22.214.171.124.
Limited by the size of the AT bin files, only 1024+1024 flash map is supported by default. Therefore, please choose 16Mbit/32Mbit-C1 flash size when flashing these AT bin files with Espressif's Flash Download Tools.
New Features and Optimizations
Add partition table to manage flash partition, more details are in documents/CN/Partition Table 说明.md or documents/EN/Partition Table.md.
Add WiFi APIs to set sleep level of modem sleep and light sleep.
Add signalling measurement feature
Support random DHCP transaction id
Add libhal.a for the new compiler
Add command AT+SYSMSG_DEF and AT+SYSMSG_CUR to instead of AT+SYSMSG.
Add AT+CIPCLOSEMODE to select TCP close mode.
Add a parameter in AT+CWJAP_CUR and AT+CWJAP_DEF to disable the connection to open/wep router
Add AT+CIPRECVLEN to get the length of received data in passive receiving mode.
Add AT+CIPRECVMODE to set TCP receive mode.
Add commands to configure SSL client authentication
Replace ssl with mbedtls in AT
Make SmartConfig optional, users can disable it in application for smaller bin size and more memory.
Disable AT+RFAUTOTRACE command.
Fix issue that system crashes when calling os_printf_plus in interrupt handler.
fix issue that mbedtls cannot set the fragment to be 2048.
fix issue that OTA may crash with some server.
Fix issue that beacon info does not update after wifi_station_scan.
Fix softAP compatibility issue.
Fix issue that fails to scan hidden AP in station mode.
Fix issue that GPIO related commands always return OK even without GPIO number.
Fix issue that extra 0x0A displayed in SNTP time string