ESP32 Wi-Fi Programming Model
------------------------------
-The ESP32 Wi-Fi programming model is depicted as follows::
-
- default handler user handler
- ----------- ------------- -------------
- | | event | | callback or | |
- | TCPIP | ---------> | event | ----------> | application |
- | stack | | task | event | task |
- ----------- ------------- -------------
- /|\ |
- | |
- event | |
- | |
- | |
- ------------- |
- | | |
- | Wi-Fi Driver|/__________________|
- | |\ API call
- | |
- -------------
+The ESP32 Wi-Fi programming model is depicted as follows:
+
+.. blockdiag::
+ :caption: Wi-Fi Programming Model
+ :align: center
+
+ blockdiag wifi-programming-model {
+
+ # global attributes
+ node_height = 60;
+ node_width = 100;
+ span_width = 100;
+ span_height = 60;
+ default_shape = roundedbox;
+ default_group_color = none;
+
+ # node labels
+ TCP_STACK [label="TCP\n stack", fontsize=12];
+ EVNT_TASK [label="Event\n task", fontsize=12];
+ APPL_TASK [label="Application\n task", width = 120, fontsize=12];
+ WIFI_DRV [label="Wi-Fi\n Driver", width = 120, fontsize=12];
+ KNOT [shape=none];
+
+ # node connections + labels
+ TCP_STACK -> EVNT_TASK [label=event];
+ EVNT_TASK -> APPL_TASK [label="callback\n or event"];
+
+ # arrange nodes vertically
+ group {
+ label = "default handler";
+ orientation = portrait;
+ EVNT_TASK <- WIFI_DRV [label=event];
+ }
+
+ # intermediate node
+ group {
+ label = "user handler";
+ orientation = portrait;
+ APPL_TASK -- KNOT;
+ }
+ WIFI_DRV <- KNOT [label="API\n call"];
+ }
+
The Wi-Fi driver can be considered a black box that knows nothing about high-layer code, such as the
TCPIP stack, application task, event task, etc. All the Wi-Fi driver can do is receive API calls from the high layer,
ESP32 Wi-Fi Station General Scenario
---------------------------------------
-Below is a "big scenario" which describes some small scenarios in Station mode::
-
- --------- --------- --------- --------- ---------
- | Main | | app | | Event | | LwIP | | Wi-Fi |
- | task | | task | | task | | task | | task |
- --------- --------- --------- --------- ---------
- | | | | | ---
- | 1.1> create/init LwIP | | | |
- |---------------------------------------------------------->| | |
- | 1.2> create/init event | | |
- |-------------------------------------->| | | 1. Init Phase
- | | 1.3> create/init Wi-Fi | |
- |----------------------------------------------------------------------------->| |
- | 1.4> create app task | | | |
- |------------------>| | | | |
- | | | | | ---
- | | | | | |
- | | | | |
- | | 2> configure Wi-Fi | | 2. Configure Phase
- |----------------------------------------------------------------------------->|
- | | | | | |
- | | | | | ---
- | | 3.1> start Wi-Fi | | |
- |----------------------------------------------------------------------------->|
- | | | 3.2 > SYSTEM_EVENT_STA_START | 3. Start Phase
- | | |<-------------------------------------|
- | 3.3> SYSTEM_EVENT_STA_START | | |
- | |<------------------| | | ---
- | | | | | |
- | | | | | |
- | | 4.1> connect wifi | | |
- | |--------------------------------------------------------->| 4. Connect Phase
- | | | 4.2> SYSTEM_EVENT_STA_CONNECTED | |
- | | |<-------------------------------------| |
- | 4.3> SYSTEM_EVENT_STA_CONNECTED | | |
- | |<------------------| | | ---
- | | | | | |
- | | | | | |
- | | 5.1> start DHCP client | | |
- | | |------------------>| | |
- | | 5.2> SYSTEM_EVENT_STA_GOT_IP | |
- | | |<------------------| |
- | 5.3> SYSTEM_EVENT_STA_GOT_IP | | 5. Got IP Phase
- | |<------------------| | |
- | |----- | | | |
- | | | 5.4> socket related init | | |
- | |<---- | | | |
- | | | | | ---
- | | | 6.1> SYSTEM_EVENT_STA_DISCONNECTED | |
- | | |<-------------------------------------|
- | 6.2> SYSTEM_EVENT_STA_DISCONNECTED | | 6. Disconnect Phase
- | |<------------------| | |
- | |----- | | | |
- | | | 6.3> disconnect handling | | |
- | |<---- | | | ---
- | | | | | |
- | | 7.1> SYSTEM_EVENT_STA_GOT_IP | |
- | | |<------------------| | |
- | 7.2> SYSTEM_EVENT_STA_GOT_IP | |
- | |<------------------| | | 7. IP change phase
- | |----- | | |
- | | | 7.3> socket error handling | | |
- | |<---- | | | |
- | | | | | ---
- | | 8.1> disconnect Wi-Fi | | |
- | |--------------------------------------------------------->|
- | | 8.2> stop Wi-Fi | | 8. Deinit phase
- | |--------------------------------------------------------->|
- | | 8.3> deinit Wi-Fi | | |
- | |--------------------------------------------------------->| |
- | | | | | ---
-
+Below is a "big scenario" which describes some small scenarios in Station mode:
+
+.. seqdiag::
+ :caption: Sample Wi-Fi Event Scenarios in Station Mode
+ :align: center
+
+ seqdiag sample-scenarios-station-mode {
+ activation = none;
+ node_width = 80;
+ node_height = 60;
+ edge_length = 140;
+ span_height = 5;
+ default_shape = roundedbox;
+ default_fontsize = 12;
+
+ MAIN_TASK [label = "Main\ntask"];
+ APP_TASK [label = "App\ntask"];
+ EVENT_TASK [label = "Event\ntask"];
+ LWIP_TASK [label = "LwIP\ntask"];
+ WIFI_TASK [label = "Wi-Fi\ntask"];
+
+ === 1. Init Phase ===
+ MAIN_TASK -> LWIP_TASK [label="1.1> Create / init LwIP"];
+ MAIN_TASK -> EVENT_TASK [label="1.2> Create / init event"];
+ MAIN_TASK -> WIFI_TASK [label="1.3> Create / init Wi-Fi"];
+ MAIN_TASK -> APP_TASK [label="1.4> Create app task"];
+ === 2. Configure Phase ===
+ MAIN_TASK -> WIFI_TASK [label="2> Configure Wi-Fi"];
+ === 3. Start Phase ===
+ MAIN_TASK -> WIFI_TASK [label="3.1> Start Wi-Fi"];
+ EVENT_TASK <- WIFI_TASK [label="3.2> SYSTEM_EVENT_STA_START"];
+ APP_TASK <- EVENT_TASK [label="3.3> SYSTEM_EVENT_STA_START"];
+ === 4. Connect Phase ===
+ APP_TASK -> WIFI_TASK [label="4.1> Connect Wi-Fi"];
+ EVENT_TASK <- WIFI_TASK [label="4.2> SYSTEM_EVENT_STA_CONNECTED"];
+ APP_TASK <- EVENT_TASK [label="4.3> SYSTEM_EVENT_STA_CONNECTED"];
+ === 5. Got IP Phase ===
+ EVENT_TASK -> LWIP_TASK [label="5.1> Start DHCP client"];
+ EVENT_TASK <- LWIP_TASK [label="5.2> SYSTEM_EVENT_STA_GOT_IP"];
+ APP_TASK <- EVENT_TASK [label="5.3> SYSTEM_EVENT_STA_GOT_IP"];
+ APP_TASK -> APP_TASK [label="5.4> socket related init"];
+ === 6. Disconnect Phase ===
+ EVENT_TASK <- WIFI_TASK [label="6.1> SYSTEM_EVENT_STA_DISCONNECTED"];
+ APP_TASK <- EVENT_TASK [label="6.2> SYSTEM_EVENT_STA_DISCONNECTED"];
+ APP_TASK -> APP_TASK [label="6.3> disconnect handling"];
+ === 7. IP Change Phase ===
+ EVENT_TASK <- LWIP_TASK [label="7.1> SYSTEM_EVENT_STA_GOT_IP"];
+ APP_TASK <- EVENT_TASK [label="7.2> SYSTEM_EVENT_STA_GOT_IP"];
+ APP_TASK -> APP_TASK [label="7.3> Socket error handling"];
+ === 8. Deinit Phase ===
+ APP_TASK -> WIFI_TASK [label="8.1> Disconnect Wi-Fi"];
+ APP_TASK -> WIFI_TASK [label="8.2> Stop Wi-Fi"];
+ APP_TASK -> WIFI_TASK [label="8.3> Deinit Wi-Fi"];
+ }
+
1. Wi-Fi/LwIP Init Phase
++++++++++++++++++++++++++++++
ESP32 Wi-Fi soft-AP General Scenario
---------------------------------------------
-Below is a "big scenario" which describes some small scenarios in Soft-AP mode::
-
- --------- --------- --------- --------- ---------
- | Main | | app | | Event | | LwIP | | Wi-Fi |
- | task | | task | | task | | task | | task |
- --------- --------- --------- --------- ---------
- | | | | |
- | | | | | ---
- | 1.1> create/init LwIP | | | |
- |---------------------------------------------------------->| | |
- | 1.2> create/init event | | |
- |-------------------------------------->| | | 1. Init Phase
- | | 1.3> create/init Wi-Fi | |
- |----------------------------------------------------------------------------->| |
- | 1.4> create app task | | | |
- |------------------>| | | | |
- | | | | | ---
- | | | | | |
- | | | | |
- | | 2> configure Wi-Fi | | 2. Configure Phase
- |----------------------------------------------------------------------------->|
- | | | | | |
- | | | | | ---
- | | | | | |
- | | 3.1> start Wi-Fi | |
- |----------------------------------------------------------------------------->| 3. Start Phase
- | | | 3.2 > SYSTEM_EVENT_AP_START |
- | | |<-------------------------------------| |
- | 3.3> SYSTEM_EVENT_AP_START | | |
- | |<------------------| | | ---
- | | | | | |
- | | | | |
- | | | 4.1> SYSTEM_EVENT_AP_STACONNECTED | 4. Connect Phase
- | | |<-------------------------------------|
- | 4.2> SYSTEM_EVENT_AP_STACONNECTED | | |
- | |<------------------| | | ---
- | | | | | |
- | | | | | |
- | | | 5.1> SYSTEM_EVENT_STA_DISCONNECTED |
- | | |<-------------------------------------| 5. Disconnect Phase
- | 5.2> SYSTEM_EVENT_STA_DISCONNECTED | |
- | |<------------------| | | |
- | |----- | | | |
- | | | 5.3> disconnect handling | | |
- | |<---- | | | ---
- | | | | | |
- | | | | | |
- | | | | | |
- | | 6.1> disconnect Wi-Fi | | |
- | |--------------------------------------------------------->|
- | | 6.2> stop Wi-Fi | | 6. Deinit phase
- | |--------------------------------------------------------->|
- | | 6.3> deinit Wi-Fi | | |
- | |--------------------------------------------------------->| |
- | | | | | ---
- | | | | |
-
+Below is a "big scenario" which describes some small scenarios in Soft-AP mode:
+
+ .. seqdiag::
+ :caption: Sample Wi-Fi Event Scenarios in Soft-AP Mode
+ :align: center
+
+ seqdiag sample-scenarios-soft-ap-mode {
+ activation = none;
+ node_width = 80;
+ node_height = 60;
+ edge_length = 140;
+ span_height = 5;
+ default_shape = roundedbox;
+ default_fontsize = 12;
+
+ MAIN_TASK [label = "Main\ntask"];
+ APP_TASK [label = "App\ntask"];
+ EVENT_TASK [label = "Event\ntask"];
+ LWIP_TASK [label = "LwIP\ntask"];
+ WIFI_TASK [label = "Wi-Fi\ntask"];
+
+ === 1. Init Phase ===
+ MAIN_TASK -> LWIP_TASK [label="1.1> Create / init LwIP"];
+ MAIN_TASK -> EVENT_TASK [label="1.2> Create / init event"];
+ MAIN_TASK -> WIFI_TASK [label="1.3> Create / init Wi-Fi"];
+ MAIN_TASK -> APP_TASK [label="1.4> Create app task"];
+ === 2. Configure Phase ===
+ MAIN_TASK -> WIFI_TASK [label="2> Configure Wi-Fi"];
+ === 3. Start Phase ===
+ MAIN_TASK -> WIFI_TASK [label="3.1> Start Wi-Fi"];
+ EVENT_TASK <- WIFI_TASK [label="3.2> SYSTEM_EVENT_AP_START"];
+ APP_TASK <- EVENT_TASK [label="3.3> SYSTEM_EVENT_AP_START"];
+ === 4. Connect Phase ===
+ EVENT_TASK <- WIFI_TASK [label="4.1> SYSTEM_EVENT_AP_STA_CONNECTED"];
+ APP_TASK <- EVENT_TASK [label="4.2> SYSTEM_EVENT_AP_STA_CONNECTED"];
+ === 5. Disconnect Phase ===
+ EVENT_TASK <- WIFI_TASK [label="5.1> SYSTEM_EVENT_STA_DISCONNECTED"];
+ APP_TASK <- EVENT_TASK [label="5.2> SYSTEM_EVENT_STA_DISCONNECTED"];
+ APP_TASK -> APP_TASK [label="5.3> disconnect handling"];
+ === 6. Deinit Phase ===
+ APP_TASK -> WIFI_TASK [label="6.1> Disconnect Wi-Fi"];
+ APP_TASK -> WIFI_TASK [label="6.2> Stop Wi-Fi"];
+ APP_TASK -> WIFI_TASK [label="6.3> Deinit Wi-Fi"];
+ }
+
ESP32 Wi-Fi Scan
------------------------
Scan All APs In All Channels(foreground)
+++++++++++++++++++++++++++++++++++++++++++
-Scenario::
-
- --------- --------- ---------
- | app | | event | | Wi-Fi |
- | task | | task | | task |
- --------- --------- ---------
- | | |
- | | |
- | 1.1> Configure country code |
- |-------------------------------------->|
- | 1.2> Scan configuration |
- |-------------------------------------->|
- | | |
- | | |
- | | |----
- | | | | 2.1> Scan channel 1
- | | |<---
- | | |----
- | | | | 2.2> Scan channel 2
- | | |<---
- | | |
- | | | .... ...
- | | |
- | | |----
- | | | | 2.x> Scan channel N
- | | |<---
- | | |
- | 3.1 SYSTEM_EVENT_SCAN_DONE |
- | |<------------------|
- | 3.2 SYSTEM_EVENT_SCAN_DONE |
- |<------------------| |
- | | |
+Scenario:
+
+.. seqdiag::
+ :caption: Foreground Scan of all Wi-Fi Channels
+ :align: center
+
+ seqdiag foreground-scan-all-channels {
+ activation = none;
+ node_width = 80;
+ node_height = 60;
+ edge_length = 160;
+ span_height = 5;
+ default_shape = roundedbox;
+ default_fontsize = 12;
+
+ APP_TASK [label = "App\ntask"];
+ EVENT_TASK [label = "Event\ntask"];
+ WIFI_TASK [label = "Wi-Fi\ntask"];
+
+ APP_TASK -> WIFI_TASK [label="1.1 > Configure country code"];
+ APP_TASK -> WIFI_TASK [label="1.2 > Scan configuration"];
+ WIFI_TASK -> WIFI_TASK [label="2.1 > Scan channel 1"];
+ WIFI_TASK -> WIFI_TASK [label="2.2 > Scan channel 2"];
+ WIFI_TASK -> WIFI_TASK [label="..."];
+ WIFI_TASK -> WIFI_TASK [label="2.x > Scan channel N"];
+ EVENT_TASK <- WIFI_TASK [label="3.1 > SYSTEM_EVENT_SCAN_DONE"];
+ APP_TASK <- EVENT_TASK [label="3.2 > SYSTEM_EVENT_SCAN_DONE"];
+ }
The scenario above describes an all-channel, foreground scan. The foreground scan can only occur in Station mode where the station does not connect to any AP. Whether it is a foreground or background scan is totally determined by the Wi-Fi driver, and cannot be configured by the application.
Scan All APs on All Channels(background)
++++++++++++++++++++++++++++++++++++++++
-Scenario::
-
- --------- --------- ---------
- | app | | event | | Wi-Fi |
- | task | | task | | task |
- --------- --------- ---------
- | | |
- | | |
- | 1.1> Configure country code |
- |-------------------------------------->|
- | 1.2> Scan configuration |
- |-------------------------------------->|
- | | |
- | | |
- | | |----
- | | | | 2.1> Scan channel 1
- | | |<---
- | | |----
- | | | | 2.2> Back to home channel H
- | | |<---
- | | |----
- | | | | 2.3> Scan channel 2
- | | |<---
- | | |----
- | | | | 2.4> Back to home channel H
- | | |<---
- | | |
- | | | .... ...
- | | |
- | | |----
- | | | | 2.x-1> Scan channel N
- | | |<---
- | | |----
- | | | | 2.x> Back to home channel H
- | | |<---
- | | |
- | 3.1 SYSTEM_EVENT_SCAN_DONE |
- | |<------------------|
- | 3.2 SYSTEM_EVENT_SCAN_DONE |
- |<------------------| |
- | | |
+Scenario:
+
+.. seqdiag::
+ :caption: Background Scan of all Wi-Fi Channels
+ :align: center
+
+ seqdiag background-scan-all-channels {
+ activation = none;
+ node_width = 80;
+ node_height = 60;
+ edge_length = 160;
+ span_height = 5;
+ default_shape = roundedbox;
+ default_fontsize = 12;
+
+ APP_TASK [label = "App\ntask"];
+ EVENT_TASK [label = "Event\ntask"];
+ WIFI_TASK [label = "Wi-Fi\ntask"];
+
+ APP_TASK -> WIFI_TASK [label="1.1 > Configure country code"];
+ APP_TASK -> WIFI_TASK [label="1.2 > Scan configuration"];
+ WIFI_TASK -> WIFI_TASK [label="2.1 > Scan channel 1"];
+ WIFI_TASK -> WIFI_TASK [label="2.2 > Back to home channel H"];
+ WIFI_TASK -> WIFI_TASK [label="2.3 > Scan channel 2"];
+ WIFI_TASK -> WIFI_TASK [label="2.4 > Back to home channel H"];
+ WIFI_TASK -> WIFI_TASK [label="..."];
+ WIFI_TASK -> WIFI_TASK [label="2.x-1 > Scan channel N"];
+ WIFI_TASK -> WIFI_TASK [label="2.x > Back to home channel H"];
+ EVENT_TASK <- WIFI_TASK [label="3.1 > SYSTEM_EVENT_SCAN_DONE"];
+ APP_TASK <- EVENT_TASK [label="3.2 > SYSTEM_EVENT_SCAN_DONE"];
+ }
The scenario above is an all-channel background scan. Compared to `Scan All APs In All Channels(foreground)`_ , the difference in the all-channel background scan is that the Wi-Fi driver will scan the back-to-home channel for 30 ms before it switches to the next channel to give the Wi-Fi connection a chance to transmit/receive data.
Scan for a Specific AP in All Channels
+++++++++++++++++++++++++++++++++++++++
-Scenario::
-
- --------- --------- ---------
- | app | | event | | Wi-Fi |
- | task | | task | | task |
- --------- --------- ---------
- | | |
- | | |
- | 1.1> Configure country code |
- |-------------------------------------->|
- | 1.2> Scan configuration |
- |-------------------------------------->|
- | | |
- | | |
- | | |----
- | | | | 2.1> Scan channel C1
- | | |<---
- | | |----
- | | | | 2.2> Scan channel C2
- | | |<---
- | | |
- | | | ...
- | | |
- | | |----
- | | | | 2.x> Scan channel CN, or the AP is found
- | | |<---
- | | |
- | 3.1 SYSTEM_EVENT_SCAN_DONE |
- | |<------------------|
- | 3.2 SYSTEM_EVENT_SCAN_DONE |
- |<------------------| |
- | | |
+Scenario:
+
+.. seqdiag::
+ :caption: Scan of specific Wi-Fi Channels
+ :align: center
+
+ seqdiag scan-specific-channels {
+ activation = none;
+ node_width = 80;
+ node_height = 60;
+ edge_length = 160;
+ span_height = 5;
+ default_shape = roundedbox;
+ default_fontsize = 12;
+
+ APP_TASK [label = "App\ntask"];
+ EVENT_TASK [label = "Event\ntask"];
+ WIFI_TASK [label = "Wi-Fi\ntask"];
+
+ APP_TASK -> WIFI_TASK [label="1.1 > Configure country code"];
+ APP_TASK -> WIFI_TASK [label="1.2 > Scan configuration"];
+ WIFI_TASK -> WIFI_TASK [label="2.1 > Scan channel C1"];
+ WIFI_TASK -> WIFI_TASK [label="2.2 > Scan channel C2"];
+ WIFI_TASK -> WIFI_TASK [label="..."];
+ WIFI_TASK -> WIFI_TASK [label="2.x > Scan channel CN, or the AP is found"];
+ EVENT_TASK <- WIFI_TASK [label="3.1 > SYSTEM_EVENT_SCAN_DONE"];
+ APP_TASK <- EVENT_TASK [label="3.2 > SYSTEM_EVENT_SCAN_DONE"];
+ }
This scan is similar to `Scan All APs In All Channels(foreground)`_. The differences are:
----------------------------------------
Generally, the application does not need to care about the connecting process. Below is a brief introduction to the process for those who are really interested.
-Scenario::
-
- --------- --------- ---------
- | Event | | Wi-Fi | | AP |
- | task | | task | | |
- --------- --------- ---------
- | | |
- | | | ---
- | |---- | |
- | | | 1.1> Scan |
- | |<--- | Scan phase
- | 1.2> SYSTEM_EVENT_STA_DISCONNECTED |
- |<------------------| | |
- | | | ---
- | | | |
- | 2.1> Auth Request | |
- | |------------------>| |
- | 2.2> SYSTEM_EVENT_STA_DISCONNECTED |
- |<------------------| | Auth phase
- | 2.3> Auth Response |
- | |<------------------| |
- | 2.4> SYSTEM_EVENT_STA_DISCONNECTED | |
- |<------------------| | ---
- | | | |
- | | 3.1 Assoc Request | |
- | |------------------>| |
- | 3.2> SYSTEM_EVENT_STA_DISCONNECTED |
- |<------------------| | Assoc phase
- | 3.3 Assoc Response |
- | |<------------------| |
- | 3.4> SYSTEM_EVENT_STA_DISCONNECTED | |
- |<------------------| | |
- | | | ---
- | | | |
- | | 4.1> 1/4 EAPOL | |
- | |<------------------| |
- | 4.2> SYSTEM_EVENT_STA_DISCONNECTED | |
- |<------------------| | |
- | | 4.3> 2/4 EAPOL | |
- | |------------------>| |
- | 4.4> SYSTEM_EVENT_STA_DISCONNECTED |
- |<------------------| | 4-way handshake phase
- | | 4.5> 3/4 EAPOL |
- | |<------------------| |
- | 4.6> SYSTEM_EVENT_STA_DISCONNECTED | |
- |<------------------| | |
- | | 4.7> 4/4 EAPOL | |
- | |------------------>| |
- | 4.8> SYSTEM_EVENT_STA_DISCONNECTED | |
- |<------------------| | |
- | | | |
- | 4.9> SYSTEM_EVENT_STA_DISCONNECTED | |
- |<------------------| | ---
- | | |
+Scenario:
+
+.. seqdiag::
+ :caption: Wi-Fi Station Connecting Process
+ :align: center
+
+ seqdiag station-connecting-process {
+ activation = none;
+ node_width = 80;
+ node_height = 60;
+ edge_length = 160;
+ span_height = 5;
+ default_shape = roundedbox;
+ default_fontsize = 12;
+
+ EVENT_TASK [label = "Event\ntask"];
+ WIFI_TASK [label = "Wi-Fi\ntask"];
+ AP [label = "AP"];
+
+ === 1. Scan Phase ===
+ WIFI_TASK -> WIFI_TASK [label="1.1 > Scan"];
+ EVENT_TASK <- WIFI_TASK [label="1.2 > SYSTEM_EVENT_STA_DISCONNECTED"];
+ === 2. Auth Phase ===
+ WIFI_TASK -> AP [label="2.1 > Auth request"];
+ EVENT_TASK <- WIFI_TASK [label="2.2 > SYSTEM_EVENT_STA_DISCONNECTED"];
+ WIFI_TASK <- AP [label="2.3 > Auth response"];
+ EVENT_TASK <- WIFI_TASK [label="2.4 > SYSTEM_EVENT_STA_DISCONNECTED"];
+ === 3. Assoc Phase ===
+ WIFI_TASK -> AP [label="3.1 > Assoc request"];
+ EVENT_TASK <- WIFI_TASK [label="3.2 > SYSTEM_EVENT_STA_DISCONNECTED"];
+ WIFI_TASK <- AP [label="3.3 > Assoc response"];
+ EVENT_TASK <- WIFI_TASK [label="3.4 > SYSTEM_EVENT_STA_DISCONNECTED"];
+ === 4. 4-way Handshake Phase ===
+ WIFI_TASK -> AP [label="4.1 > 1/4 EAPOL"];
+ EVENT_TASK <- WIFI_TASK [label="4.2 > SYSTEM_EVENT_STA_DISCONNECTED"];
+ WIFI_TASK -> AP [label="4.3 > 2/4 EAPOL"];
+ EVENT_TASK <- WIFI_TASK [label="4.4 > SYSTEM_EVENT_STA_DISCONNECTED"];
+ WIFI_TASK -> AP [label="4.5 > 3/4 EAPOL"];
+ EVENT_TASK <- WIFI_TASK [label="4.6 > SYSTEM_EVENT_STA_DISCONNECTED"];
+ WIFI_TASK -> AP [label="4.7 > 4/4 EAPOL"];
+ EVENT_TASK <- WIFI_TASK [label="4.8 > SYSTEM_EVENT_STA_DISCONNECTED"];
+ EVENT_TASK <- WIFI_TASK [label="4.9 > SYSTEM_EVENT_STA_DISCONNECTED"];
+ }
+
Scan Phase
+++++++++++++++++++++
Wi-Fi Buffer Configure
+++++++++++++++++++++++
-If you are going to modify the default number or type of buffer, it would be helpful to also have an overview of how the buffer is allocated/freed in the data path. The following diagram shows this process in the TX direction::
+If you are going to modify the default number or type of buffer, it would be helpful to also have an overview of how the buffer is allocated/freed in the data path. The following diagram shows this process in the TX direction:
+
+.. blockdiag::
+ :caption: TX Buffer Allocation
+ :align: center
+
+ blockdiag buffer_allocation_tx {
+
+ # global attributes
+ node_height = 60;
+ node_width = 100;
+ span_width = 50;
+ span_height = 20;
+ default_shape = roundedbox;
+
+ # labels of diagram nodes
+ APPL_TASK [label="Application\n task", fontsize=12];
+ LWIP_TASK [label="LwIP\n task", fontsize=12];
+ WIFI_TASK [label="Wi-Fi\n task", fontsize=12];
+
+ # labels of description nodes
+ APPL_DESC [label="1> User data", width=120, height=25, shape=note, color=yellow];
+ LWIP_DESC [label="2> Pbuf", width=120, height=25, shape=note, color=yellow];
+ WIFI_DESC [label="3> Dynamic (Static)\n TX Buffer", width=150, height=40, shape=note, color=yellow];
+
+ # node connections
+ APPL_TASK -> LWIP_TASK -> WIFI_TASK
+ APPL_DESC -> LWIP_DESC -> WIFI_DESC [style=none]
+ }
- ------------- ------------- -------------
- | Application | | LwIP | | Wi-Fi |
- | task | ---------> | task | ---------> | task |
- ------------- ------------- -------------
- 1> User data 2> Pbuf 3> Dynamic (Static) TX Buffer
Description:
- The application allocates the data which needs to be sent out.
- The application calls TCPIP-/Socket-related APIs to send the user data. These APIs will allocate a PBUF used in LwIP, and make a copy of the user data.
- When LwIP calls a Wi-Fi API to send the PBUF, the Wi-Fi API will allocate a "Dynamic Tx Buffer" or "Static Tx Buffer", make a copy of the LwIP PBUF, and finally send the data.
-The following diagram shows how buffer is allocated/freed in the RX direction::
-
- ------------- ------------- ------------- -------------
- | Application | | LwIP | | Wi-Fi | | Wi-Fi |
- | Task | <--------- | task | <--------- | task | <--------- | Interrupt |
- ------------- ------------- ------------- -------------
- 4> User data 3> Pbuf 2> Dynamic RX Buffer 1> Static RX Buffer
+The following diagram shows how buffer is allocated/freed in the RX direction:
+
+.. blockdiag::
+ :caption: RX Buffer Allocation
+ :align: center
+
+ blockdiag buffer_allocation_rx {
+
+ # global attributes
+ node_height = 60;
+ node_width = 100;
+ span_width = 40;
+ span_height = 20;
+ default_shape = roundedbox;
+
+ # labels of diagram nodes
+ APPL_TASK [label="Application\n task", fontsize=12];
+ LWIP_TASK [label="LwIP\n task", fontsize=12];
+ WIFI_TASK [label="Wi-Fi\n task", fontsize=12];
+ WIFI_INTR [label="Wi-Fi\n interrupt", fontsize=12];
+
+ # labels of description nodes
+ APPL_DESC [label="4> User\n Data Buffer", height=40, shape=note, color=yellow];
+ LWIP_DESC [label="3> Pbuf", height=40, shape=note, color=yellow];
+ WIFI_DESC [label="2> Dynamic\n RX Buffer", height=40, shape=note, color=yellow];
+ INTR_DESC [label="1> Static\n RX Buffer", height=40, shape=note, color=yellow];
+
+ # node connections
+ APPL_TASK <- LWIP_TASK <- WIFI_TASK <- WIFI_INTR
+ APPL_DESC <- LWIP_DESC <- WIFI_DESC <- INTR_DESC [style=none]
+ }
Description:
projects / esp-idf / commitdiff