Module net

Expand description

WiFi radio and TCP/IP stack (esp-radio + embassy-net).

One of two modes is chosen at boot from Config::connection:

Access point (default): static IPv4 192.168.4.1/24 plus a DHCP server handing out leases to AP clients (dhcp).
Station: joins the configured network and gets its address via DHCP. If the association does not come up within STA_CONNECT_TIMEOUT — or the DHCP lease does not arrive within STA_DHCP_TIMEOUT — the device switches to AP mode instead so it stays reachable. After a successful station boot, a lost association is retried every STA_RECONNECT_DELAY (the device then stays in station mode, so reachability depends on the AP coming back).

The event loop at the end of task doubles as the controller keep-alive: dropping WifiController de-initializes the radio.

In both modes the HTTP/WebSocket server (http, ws) is started on the stack once the interface is up.

Modules§

AP_IP: Static IPv4 address of the access point — also the DHCP server identifier handed out in option 54.
AP_PREFIX: Prefix length of the access-point subnet.
SOCKETS 🔒: Socket slots in the network stack — four HTTP connection slots plus the DHCP server (AP mode) or DHCP client (station mode), with headroom.
STA_CONNECT_TIMEOUT 🔒: Maximum time to wait for a station association before falling back to access-point mode.
STA_DHCP_TIMEOUT 🔒: Maximum time to wait for the station DHCP lease before falling back to access-point mode.
STA_RECONNECT_DELAY 🔒: Pause between station re-association attempts after a runtime disconnect (the boot-time fallback does not apply here — the device keeps retrying).

STACK_AP 🔒: Socket storage for the AP-mode stack, kept separate from STACK_STA so a DHCP-timeout fallback can bring the AP up beside the idle station stack (both cells always cost ~2 KiB of .bss).
STACK_STA 🔒: Socket storage for the station-mode stack — used when the boot path attempts a station lease (the cell is abandoned if DHCP times out).

ap_ssid 🔒: Resolves the AP SSID: the configured one, or a MAC-derived default.
build_ap 🔒: Builds the access-point configuration for esp-radio.
build_sta 🔒: Builds the station configuration for esp-radio.
runner_task 🔒: Drives the network device event loop (spawned by spawn_runner).
spawn_runner 🔒: Spawns the embassy-net driver loop (logged, non-fatal on failure).
stack_seed 🔒: Deterministic seed for the network stack, derived from the factory MAC address (keeps ephemeral port selection stable across reboots).
start_ap 🔒: Brings up the embassy-net stack on the access-point interface with a static address and spawns the DHCP server for AP clients.
start_station 🔒: Brings up the embassy-net stack on the station interface with a DHCP client and waits for the lease.
task: Network task: brings up WiFi in station or AP mode and runs the event loop.
try_station 🔒: Races the station association against STA_CONNECT_TIMEOUT.