Problem with Spi Protocol stack

[LuciaferKelvin]

hello there. I have a problem with mcu spi Protocol stack , My mcu work as host .The project have a F429 project with RTOS. How can I using the spi function without rtos? I had not find out any information with how to framing. And I am sure that the spi interface is work ok ,I had using ESP_LOGI function log what am I send by mcu. Could you tell me how to framing and what is the setting step ?

[LuciaferKelvin]

Thank you very much

[LuciaferKelvin]

by the way , ESP is ESP32C3-MINI-1

[mantriyogesh]

@LuciaferKelvin

Thank you for your query. I assume F429 means STM32 board like STM32F429ZI. You can use any RTOS for this. You might have to port the 'ioc' file using STM32CubeMX first.

How can I using the spi function without rtos?

We have never tried this. but if you are certain, you can go ahead. SPI and GPIOs should be able to work. Porting from RTOs to No-RTOS may take huge time (if you have not done already).

I had not find out any information with how to framing

I did not understand the question correctly. Are you asking about frame formation used ESP-Hosted (in between ESP and STM32)? If yes, you can check https://github.com/espressif/esp-hosted/tree/master/esp_hosted_fg#42-transport-layer-communication-protocol & esp_hosted_fg/common/include/adapter.h https://github.com/espressif/esp-hosted/blob/3769eea28bbbc59d8ea2aff425d62564b7fb3e68/esp_hosted_fg/common/include/adapter.h#L23-L40

what is the setting step?

I really have no clue what is meant by this. Should I assume project settings/properties to be used for STM32CubeIDE? If so, the settings should be same. You just might have to add symbol similar to: Right click on project, go to project properties-> C/C++ general -> Paths and symbols -> Select tab 'Symbols' -> add your STM32's debug symbol like 'STM32F469xx'. You might have to search and replace 'STM32F469xx' with your new symbol.

Rest change in settings like Station's SSID password etc can be found on the documentation as you follow, https://github.com/espressif/esp-hosted/tree/master/esp_hosted_fg#22-setup-with-mcu-host

[LuciaferKelvin]

Thank you for your response.

what is setting step?

For example ， if I want to the esp32 working in the station mode，what is the setting steps should I using spi send to esp32. such as using the struct esp_payload_header and send frame: step 1:0x00 0x02 0x0c 0x00 0x00 0x00 0x00

I have not idea with how to set the commiuncation with esp32 , the frame like step 1 I had send to esp ,and I also loged the reasult,it seems work,but how should i do next.

You might have to port the 'ioc' file using STM32CubeMX first.

I had try to open the ioc by stmcubeide ,but it only has the base project of stm469 hardware driver.Like the pic.

SPI and GPIOs should be able to work. I am sure that spi is work normal. This information was loged on the esp project by uart.

[LuciaferKelvin]

,but how should i do next. like how to set up the MAC,how to get the SSID,then how to set the SSID,how to set the password and so on.

[mantriyogesh]

I think better to read up the documentation first. start from https://github.com/espressif/esp-hosted and try to explore esp_hosted_fg and MCU based readme first. Actually we tried to explain in stepwise manner how is the -

1. Design
2. Architecture
3. Code organization
4. Project settings & tuning
5. Demo arping application

I know it is little time taking, but I assure it is worthwhile to get aligned with documentation. Then you start to port your solution for your STM32. We will be here to help you out

[LuciaferKelvin]

OK，Maybe some important information I had miss, I will read it again.Thank you.

[mantriyogesh]

Hello @LuciaferKelvin

Do connect if you face any issues. Just to brief a little, the hooks are available to integrate your network stack. you can start from a demo task of arp-ping https://github.com/espressif/esp-hosted/blob/3769eea28bbbc59d8ea2aff425d62564b7fb3e68/esp_hosted_fg/host/stm32/app/app_main.c#L341-L363 and dig down how the packets are sent or received.

The framing and all underlying packing, handling of messages are already taken care. When you just implement the hooks, you can use your network stack for your use case.

There are multiple users who have integrated their own stacks easily, and you can even find references in this project's issues or PRs.

Let us know if you are unsure of any thing, we will definitely try to get you a solution.

[LuciaferKelvin]

Fine ,Thank you very much.

[LuciaferKelvin]

hello@mantriyogesh I had add my function to send the package to ESP. But ESP always reboot when I send one package. I used get_ap_scan_list() function in control_utils.c to make the msg package.And I using the thirdpart Lwip,so I just need the real msg for netdev. I have not use the ARP ex. in the demo. The debug msg as show: Actual data as follow: ESP accpt msg as follow: ESP error log as follow: ESP reboot log as follow:

when I log the msg as character: I saw "crltResp",but ESP log that "No registered endpoint for CtrlResp",

Is that means the command I am use is wrong ? I have no idea with thar.But I haven`t change anything when the msg packed. It is all form the demo.

[mantriyogesh]

Okay.

1. Can you please show the code you have added a packet in detail?
2. Are you using ESP binaries ? If yes, which version? In that case, are you using the source code tar bundle available with release at Linux side building?

[LuciaferKelvin]

1. The code detaill I can`t show here,I can tell the packeting process: get_ap_scan_list()->test_get_available_wifi()->wifi_app_scan_list(req)->CTRL_SEND_REQ(CTRL_REQ_GET_AP_SCAN_LIST) ->transport_pserial_send(tx_data, tx_len)->serial_drv_write(serial_handle, write_buf, count, &count)->serial_ll_if_g->fops ->write(serial_ll_if_g, buf, in_count)->ESP_SendToSlave(serial_ll_hdl->if_type,serial_ll_hdl->if_num, wbuffer, wlen) all of the funciton base on demo except ESP_SendToSlave，but that funciton same with demo,I just change the hardware send function. 2.I use VSCODE ESP-IDF to compling the esp project(esp-hosted-release-v0.4),it from https://github.com/espressif/esp-hosted/tree/release/v0.4#22-getting-started-with-mcu-host

[mantriyogesh]

@ajita02 Do you think that host is on > 0.4 and ESP on 0.4? I strongly suspect that because 'ctrlResp' I think is not present in release/v0.4.

[mantriyogesh]

@LuciaferKelvin Can you please let us know output of command $ git commit when ran at ESP-Hosted repo where MCU code is built?

[LuciaferKelvin]

I cant ,cause I download it with zip,not for git clone,Is there any other way to show the inforamtion ? by the way , ESP base I using the https://github.com/espressif/esp-hosted/tree/release/v0.4#22-getting-started-with-mcu-host but the mcu base I using the https://github.com/espressif/esp-hosted which you had told me ,Is there any possibility may be cause this problem？

[LuciaferKelvin]

My network is not very well , it always lost when using "git clone" command ,so I download it with zip. QAQ

[mantriyogesh]

,cause I download it with zip,not for git clone,Is there any other way to show the infor

yes. ESP and MCU should use same code at any point of time.

[LuciaferKelvin]

hello there , I had rebuild my project. Now I can using the normal command to commiuncate with esp. but when I start the softap service ,the ap sevice has stop automatically like the pic. Is there any reponse need I feed back to esp?

[mantriyogesh]

Can you please send:

1. Complete logs at both sides: ESP - ESP log (textual) Host - (1) dmesg log or /var/log/kern.log (2) test run log
2. Is it possible to share the application code, to understand if there are any problems (you can use minimal demo application as well, to showcase what you want to do)
3. Is it possible to use FG release 0.0.5 -> source code for both ESP flashing and host driver building

[LuciaferKelvin]

1. here is the esp log . esp-log.txt
2. no ,it isnt.for esp host is parts of the project , i cant make it become a independent project.
3. time will not allowed to transplant thrid times

[LuciaferKelvin]

this function I saw that just using two commands to start the ap sevice,one is get the mac replace host save mac.another is start the ap service .

[mantriyogesh]

Please share

1. ESP side code's git commit version
2. Host side code's git commit version
3. host side logs either dmesg or /var/log/kern.log. Please attach complete log.

[mantriyogesh]

As you are using old code, we need to understand exact code base you are referring to. We have solved many issues in this code part.

Requesting you to share the above three things.

[LuciaferKelvin]

Thanks for you patient.I had solved this problem.It haven`t any wrong in fact.The antenna is not connected into the esp when I test it.Although the log report "soft ap stop handle stop",but the sevice also start up successfully.

[mantriyogesh]

@LuciaferKelvin

Okay. Thanks for the update. In case you face any issues in future, let us know in this thread.

[LuciaferKelvin]

hello there, I have meet with a problem.First this problem have nothing to do with ESP.I have no idea to fixed that ,So I want to ask your guys have ever meet with the same problem. The problem is PC client cant reicve the msg from esp , but I can get the msg by wireshake .In that msg ,all the paramter is right ,and wireshake could distinguish that msg is the second times hand shake msg for PC client,but the PC client cant recive it . The esp could recive the first times hand shake msg. In this pic ,the 192.168.33.1 is the mcu host ,192.168.33.10 is the PC client.

Do your guys has any idea about this question? Thanks a lot .I am sure that the fire wall is not effect the connection ,it has not intercept the msg.

[mantriyogesh]

retransmissions look problem. Is it possible to localize if the packets even reach to ESP (& till what point in host)?

[LuciaferKelvin]

In the wireshark , I can sure that the ESP recive the first times hand shake msg when PC send that. then mcu send the second times hand shake msg to the PC by ESP .I am also sure ESP send that msg success because wireshark had capture the second tims msg.But I am not sure if the msg reach in the client, seems the client had not get the second times hand shark msg ,then both of PC and mcu retransmission the first times hand shake msg and the second times hand shake msg. I do not known the reason why the wireshark can capture the msg but the client can not get the second times msg. I have no idea to location the msg was lost in which step.

[mantriyogesh]

Some questions:

1. Where is the wireshark running? Is it sniffer capture?
2. Can you please explain through some block diagram, what you are trying to exactly do?

Once we understand the scenario better, can help in localising the problem.

[LuciaferKelvin]

1. wireshark is running in the pc .yes .
2. I had solved with the last question which talk to you in the issues. The new question is in make a tcp/ip connection. pc is the client, mcu is the server. like this them can`t make a tcp/ip connection.

[mantriyogesh]

Lets us take step by step.

Actually I wanted to know how the PC is connected or communicating to MCU.

I assume,

PC <-- wifi -->  MCU host (exposing ESP softAP)

i.e.

PC <-- wifi --> ESP softAP <== ESP-Hosted (SPI slave) ==> MCU host (SPI master)

Is this correct?

[LuciaferKelvin]

sure ,it is right

[mantriyogesh]

Now as I understand, MCU host is up with ESP-Hosted.

1. So, control API have started the softAP at MCU host. Can you please get me log at MCU host?
2. How are the IPs assigned at PC and MCU host (static or dhcp)?
3. Are you able to ping 192.168.33.1 (MCU host) from 192.168.33.10 (PC)?

[mantriyogesh]

4. Have you integrated the network stack at MCU host?

5. I think, use the project as is first, check if arping are reached to & fro. This would confirm if ESP-Hosted is ported and functioning correctly.

6. if step (5) is pass and Integrate the network stack. Test ping first.

[LuciaferKelvin]

1.Actually I had using the lwip to manager the softap ,what kind of log do you want ? 2.I had add the dhcp server to mcu host , the pc ip is assign by mcu host. 3.yes ,but it must open the lwip cfg

[LuciaferKelvin]

and the mcu host work normal, it is the ip assign by mcu host

[mantriyogesh]

Hosted scope

If you see, https://github.com/espressif/esp-hosted/blob/master/esp_hosted_fg/host/stm32/app/app_main.c#L318-L332 here we receive packet and manually check if received packet is destined for us? if yes, we just send arping response.

Now your network stack will replace this functionality for handling layer 3 packets. So if you are able to send/receive ping even with checksum disabled as you pointed, the ESP-Hosted is confirmed to work fine.

The network stack porting is kept outside scope as every network stack has some adaptations and limitation.

Outside Hosted scope (network stack porting)

Caution: A little technical discussion ahead & take it slow to understand.

• Worth to pay attention to alignments used and the packets received are aligned.

• Please pay attention if the network stack wherever discards header and access remaining packet from next byte as as start pointer, should always be aligned

  • For example, check network stack, if when ethernet header of 14 bytes is processed & when payload is going to be accessed, it should do adjustments such that it should align to 4 bytes alignment.
  • Little out of scope for lwip, as this is netx/threadx , but relatable. Please see https://github.com/azure-rtos/netxduo/issues/17
  • In this case (just for your understanding), in process_rx_task(),

  packet_ptr -> nx_packet_prepend_ptr += 2;
  packet_ptr->nx_packet_append_ptr += 2;

  could have helped. Anyway, this is one of way to do it, it is upto user how they want to port the network stack

Coming to CHECKSUM disabled problems, you can only say that network stack is ported correctly when you are able to work with all such checksums both, enabled & disabled.

Porting the network stack usually take some time & expected to face issues like this. Nonetheless, please think from processor's point of view when accessing the packet at any layer, which might help.

Please do let us know how thing proceed for you.

[LuciaferKelvin]

ok，thanks for your patient.I am sure than esp is working fine. All this question is base on net protocol stack. To be honest,It's a little difficult.

[mantriyogesh]

I understand the pain. We plan to integrate the sample network stack for users reference. But it would definitely not in very near future because of other priority features & issues.

[LuciaferKelvin]

mantriyogesh，hello there, I had done with that project. But there has some places I don`t konw how it works.

1. When esp in sta mode connect into an ap , the ap decide the authentication mode. If the ap support WEP only and hidden, does the esp could connect to it successful?
2. in the hosted ex. code,When using soft ap mode, the esp only support four authentication mode :ESP_HOSTED_ENCRYPTION_MODEType_Open, ESP_HOSTED_ENCRYPTION_MODEType_WPA_PSK,ESP_HOSTED_ENCRYPTION_MODE__Type_WPA2_PSK,ESP_HOSTED_ENCRYPTION_MODE__Type_WPA_WPA2_PSK, Do others authentication mode not support?
3. what are the means about (is_wpa3_supported) and (has_is_wpa3_supported) in _EspHostedCmdSetAPConfig struct ? Does it means ESP could connected ap with all of the authentication mode,but the soft ap only support four authentication mode when it start server? by the way , the esp firmware I have used is Release V0.0.4.

[mantriyogesh]

1. External AP setup with WEP and hidden SSID & ESP in sta mode with correct authmode should get connected. Are you facing any issues? Logs and steps to reproduce will be helpful

2. In softAP mode, ESP supports open and wpa/wpa2/wpa3 in PSK. But as you are on old release, 0.4, you will be on old IDF (mostly 4.0). Can you please give ESP side full log? I will print IDF version used.

For softAP, idf release/v5.0 should work with open and wpa/wpa2/wpa3 in PSK authmodes. but the API is not yet updated. I will update it. authmode values can be found: https://github.com/espressif/esp-idf/blob/release/v5.0/components/esp_wifi/include/esp_wifi_types.h#L52-L64

3. Clearly naming, is_wpa3_supported to be changed to use_wpa3. I couldn't find 'has_is_wpa3_supported' in 0.0.5, may be cleaned up.

Fundamentally SoftAP doesn't support all the values of authmode. open/wpa/wpa2/wpa3 with PSK combination are only possible with SoftAP. For station, no such requirement.

By the way, idf 5.0 comes up with minimum or threshold auth mode concept, to avoid TKIP and use CCMP for WPA2 (by default)

[mantriyogesh]

Want to get notified for any station disconnection happens? 0.0.5 can get you the notifications which you had subscribed to, as they trigger.

We also strongly suggest to migrate to 0.0.5, where many bugfixes are fixed. Control path design is changed for betterment there.

[LuciaferKelvin]

1. I haven`t meet with that scene, That just I suppose if I meet with the scene how can I slove that.
2. that is the esp log

   ESP-ROM:esp32c3-api1-20210207 Build:Feb 7 2021 rst:0x1 (POWERON),boot:0xf (SPI_FAST_FLASH_BOOT) SPIWP:0xee mode:DIO, clock div:1 load:0x3fcd6100,len:0x16cc load:0x403ce000,len:0x930 load:0x403d0000,len:0x2d40 entry 0x403ce000 I (30) boot: ESP-IDF v4.4-rc1-8-g0b46ac1732-dirty 2nd stage bootloader I (30) boot: compile time 19:43:58 I (30) boot: chip revision: 3 I (34) boot.esp32c3: SPI Speed : 80MHz I (39) boot.esp32c3: SPI Mode : DIO I (43) boot.esp32c3: SPI Flash Size : 4MB I (48) boot: Enabling RNG early entropy source... I (53) boot: Partition Table: I (57) boot: ## Label Usage Type ST Offset Length I (64) boot: 0 nvs WiFi data 01 02 00009000 00004000 I (72) boot: 1 otadata OTA data 01 00 0000d000 00002000 I (79) boot: 2 phy_init RF data 01 01 0000f000 00001000 I (87) boot: 3 factory factory app 00 00 00010000 00100000 I (94) boot: 4 ota_0 OTA app 00 10 00110000 00100000 I (102) boot: 5 ota_1 OTA app 00 11 00210000 00100000 I (109) boot: End of partition table I (113) boot: Defaulting to factory image I (118) esp_image: segment 0: paddr=00010020 vaddr=3c0a0020 size=1d180h (119168) map I (145) esp_image: segment 1: paddr=0002d1a8 vaddr=3fc90800 size=02e70h ( 11888) load I (148) esp_image: segment 2: paddr=00030020 vaddr=42000020 size=93eb0h (605872) map I (246) esp_image: segment 3: paddr=000c3ed8 vaddr=3fc93670 size=00544h ( 1348) load I (246) esp_image: segment 4: paddr=000c4424 vaddr=40380000 size=10624h ( 67108) load I (264) esp_image: segment 5: paddr=000d4a50 vaddr=50000010 size=00010h ( 16) load I (269) boot: Loaded app from partition at offset 0x10000 I (269) boot: Disabling RNG early entropy source... I (284) cpu_start: Pro cpu up. I (293) cpu_start: Pro cpu start user code I (293) cpu_start: cpu freq: 160000000 I (293) cpu_start: Application information: I (295) cpu_start: Project name: network_adapter I (301) cpu_start: App version: release0.4-60-g22180f7-dirty I (308) cpu_start: Compile time: Jan 24 2022 19:43:50 I (314) cpu_start: ELF file SHA256: 15a671cd67cbaa8d... I (320) cpu_start: ESP-IDF: v4.4-rc1-8-g0b46ac1732-dirty I (327) heap_init: Initializing. RAM available for dynamic allocation: I (334) heap_init: At 3FC98DA0 len 00027260 (156 KiB): DRAM I (340) heap_init: At 3FCC0000 len 0001F060 (124 KiB): STACK/DRAM I (347) heap_init: At 50000020 len 00001FE0 (7 KiB): RTCRAM I (354) spi_flash: detected chip: generic I (358) spi_flash: flash io: dio I (362) sleep: Configure to isolate all GPIO pins in sleep state I (369) sleep: Enable automatic switching of GPIO sleep configuration I (376) coexist: coexist rom version 9387209 I (381) cpu_start: Starting scheduler. I (385) NETWORK_ADAPTER:  I (385) NETWORK_ADAPTER: ESP-Hosted Firmware version :: 0.4  I (395) NETWORK_ADAPTER: Transport used :: SPI  I (405) NETWORK_ADAPTER:  I (415) NETWORK_ADAPTER: Supported features are: I (425) NETWORK_ADAPTER: - WLAN over SPI I (425) ESP_BT: - BT/BLE I (435) ESP_BT: - HCI Over UART I (435) ESP_BT: - BLE only I (435) gpio: GPIO[5]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0  I (445) gpio: GPIO[19]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0  I (455) gpio: GPIO[8]| InputEn: 1| OutputEn: 0| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0  I (465) gpio: GPIO[18]| InputEn: 1| OutputEn: 0| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0  I (475) ESP_BT: baud rate for HCI uart :: 921600  I (485) BTDM_INIT: BT controller compile version [6881869] I (485) phy_init: phy_version 907,3369105-dirty,Dec 3 2021,14:55:12 I (545) system_api: Base MAC address is not set I (545) system_api: read default base MAC address from EFUSE I (545) BTDM_INIT: Bluetooth MAC: 34:b4:72:f3:f5:62  I (545) NETWORK_ADAPTER: ESP Bluetooth MAC addr: 34-b4-72-f3-f5-62  I (555) SPI_DRIVER: Using SPI interface I (555) gpio: GPIO[3]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0  I (565) gpio: GPIO[4]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0  I (1575) pp: pp rom version: 9387209 I (1575) net80211: net80211 rom version: 9387209

3. the version of pdf will be update at furtrue, but not now.

[LuciaferKelvin]

when esp at sta mode , the authmode will be automatic set or need program set it ? I don`t find out any struct value to set it but has_is_wpa3_supported and is_wpa3_supported.

struct defintion is that
struct  _EspHostedCmdSetAPConfig
{
  ProtobufCMessage base;
  char *ssid;
  char *pwd;
  char *bssid;
  protobuf_c_boolean has_is_wpa3_supported;
  protobuf_c_boolean is_wpa3_supported;
  protobuf_c_boolean has_listen_interval;
  int32_t listen_interval;
};

[mantriyogesh]

Single line answer: Not needed. If you are using wpa3 authmode, you still need to set is_wpa3_supported.

I got the definitions:

• Sta mode:

  • 0.4

  • https://github.com/espressif/esp-hosted/blob/74e707b604280ecb2eafa60ba5ed6993ce57b457/common/proto/esp_hosted_config.proto#L76-L81

  • 0.0.5:

  • https://github.com/espressif/esp-hosted/blob/3769eea28bbbc59d8ea2aff425d62564b7fb3e68/esp_hosted_fg/common/proto/esp_hosted_config.proto#L218-L224

• SoftAP

  • 0.4
  • https://github.com/espressif/esp-hosted/blob/74e707b604280ecb2eafa60ba5ed6993ce57b457/common/proto/esp_hosted_config.proto#L102-L110
  • 0.0.5
  • https://github.com/espressif/esp-hosted/blob/3769eea28bbbc59d8ea2aff425d62564b7fb3e68/esp_hosted_fg/common/proto/esp_hosted_config.proto#L245-L253

But you are referring to protobuf layer (lower layer), which is accessed by higher layer user space applications.

The authmode is not required to pass in station mode.

Additional information for you: IDF 5.0 keeps a provision, of threshold of authmode (in easier words, do not connect to AP even matching SSID, password but lower security) enforcement wifi_sta_config_t -> wifi_scan_threshold_t threshold. This parameter would be supported in upcoming releases of ESP-Hosted.

[LuciaferKelvin]

thank you.

[LuciaferKelvin]

hello yogesh. I have some question with ota api. The firmware i used is release v0.0.4. 1.I should use (int esp_ota_begin()) first ,then use (int esp_ota_write(uint8_t* ota_data, uint32_t ota_data_len))to transmit data, finally use (int esp_ota_end()) when I want to upgrade the firmware in esp, Is that right?

2. when using (int esp_ota_write(uint8_t* ota_data, uint32_t ota_data_len)), what is the start address ?Is the address start on 0x0000?
3. Should I must using combined firmware ?(combined firmware include bootloader ,partition-table, ota data initial,and firmware)Or need I transmit the four bin files time by time?

[mantriyogesh]

Hello @LuciaferKelvin

Are you using MCU with 0.4? With Linux, you can simply use https://github.com/espressif/esp-hosted/blob/81778f63a9d84fa46f8a907078f9e2681b391bf5/esp_hosted_fg/host/linux/host_control/c_support/test.c#L100-L103

For MCU, there are two cases.

1. If you are able to hold the network_adapter.bin fully in MCU, you can use same approach.
2. If size constraints, you can act actually transfer your image and flash part by part. you can refer python application https://github.com/espressif/esp-hosted/blob/81778f63a9d84fa46f8a907078f9e2681b391bf5/esp_hosted_fg/host/linux/host_control/python_support/py_parse/cmds.py#L299-L314 where http client library is used. For MCU with less memory or when unsure how to hold the image, it is better to go with this approach. You would want to do similar stuff in C if python not supported in MCU (with your existing HTTP client library)

[mantriyogesh]

Just for additional information about OTA: https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/system/ota.html

Hosted has done some customisation so that OTA could be done over Wi-Fi itself (with image being transferred part by part over HTTP on existing ESP-Hosted transport (say SPI)). This actually refers to point (2) in last comment.

[LuciaferKelvin]

hallo, @mantriyogesh , I had meet with new problem with firmware v0.4, In sta mode, There are probabilities esp can not work normally when the esp power on first time. It could commiucate with route or other node by arp,but can not make any connection with tcp/ip,or never reponse icmp. the esp log show it connect route successful. I had fixed that by reconnect route when esp first time power on , there have three step: 1.connected the route 2.send cmd disconnect the route 3.connected the route it could fixed that problem , but I have no idea about what is the reason make this sence.