forgefixture: the bench actuator's firmware

An ESP32-S3 DevKitC-1 on the bench network drives three relays at the machine's connectors so the acceptance tool can open the lid loop, pull the interlock loop and press the button with nobody in the room. Two contacts are normally closed in loops the safety chain already reads, the third is normally open across the button input and only ever pulsed (20 to 500 ms, the end armed before the line rises); every line is low at boot and after any reset, the task watchdog panics and reboots, and the button channel needs a jumper. HTTP on port 80 under a key in X-Fixture-Key; the hostname announced over DHCP and mDNS. ESP-IDF v5.5 native, the mDNS component pinned in dependencies.lock; fixture.env (git-ignored) is the one input: the wifi, the key, the hostname. fixture.sh builds with idf.py or in the espressif/idf container, flashes with esptool from pip. The decisions that need no hardware live in policy.c with a gcc host test; CI runs it and builds the firmware in the pinned container.
2026-09-27 16:51:12 -07:00 · 2026-08-23 14:15:53 -04:00
parent 335c6dea9d
commit 8ee4ee3946
23 changed files with 1269 additions and 0 deletions
@@ -0,0 +1,119 @@
+/*
+ * forgefixture wifi (see wifi.h).
+ *
+ * (C) Copyright 2026
+ * Scott Wiederhold, s.e.wiederhold@gmail.com
+ * SPDX-License-Identifier: MIT
+ */
+#include "wifi.h"
+
+#include <string.h>
+
+#include "esp_event.h"
+#include "esp_log.h"
+#include "esp_netif.h"
+#include "esp_wifi.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "mdns.h"
+
+static const char *TAG = "wifi";
+
+static esp_netif_t *s_netif;
+static volatile bool s_connected;
+static esp_ip4_addr_t s_ip;
+static char s_hostname[32];
+
+static void on_wifi(void *arg, esp_event_base_t base, int32_t id, void *data)
+{
+    (void)arg;
+    (void)data;
+    if (id == WIFI_EVENT_STA_START) {
+        esp_wifi_connect();
+    } else if (id == WIFI_EVENT_STA_DISCONNECTED) {
+        const wifi_event_sta_disconnected_t *d = data;
+        s_connected = false;
+        ESP_LOGW(TAG, "disconnected (reason %d), reconnecting", d ? d->reason : -1);
+        /* A short pause keeps a wrong passphrase from becoming a storm;
+         * the event loop task tolerates it. */
+        vTaskDelay(pdMS_TO_TICKS(1000));
+        esp_wifi_connect();
+    }
+}
+
+static void on_ip(void *arg, esp_event_base_t base, int32_t id, void *data)
+{
+    (void)arg;
+    (void)base;
+    if (id == IP_EVENT_STA_GOT_IP) {
+        const ip_event_got_ip_t *ev = data;
+        s_ip = ev->ip_info.ip;
+        s_connected = true;
+        ESP_LOGI(TAG, "joined: " IPSTR " as %s.local", IP2STR(&ev->ip_info.ip), s_hostname);
+    } else if (id == IP_EVENT_STA_LOST_IP) {
+        s_connected = false;
+        ESP_LOGW(TAG, "address lost");
+    }
+}
+
+static void mdns_start(const char *hostname)
+{
+    ESP_ERROR_CHECK(mdns_init());
+    ESP_ERROR_CHECK(mdns_hostname_set(hostname));
+    ESP_ERROR_CHECK(mdns_instance_name_set("ForgeFIRM bench fixture"));
+    mdns_txt_item_t txt[] = {
+        {"device", "forgefixture"},
+        {"channels", "lid,interlock,button"},
+    };
+    ESP_ERROR_CHECK(mdns_service_add(NULL, "_forgefixture", "_tcp", 80, txt, 2));
+    ESP_ERROR_CHECK(mdns_service_add(NULL, "_http", "_tcp", 80, txt, 2));
+}
+
+void wifi_start(const char *hostname, const char *ssid, const char *psk)
+{
+    strncpy(s_hostname, hostname, sizeof(s_hostname) - 1);
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+    s_netif = esp_netif_create_default_wifi_sta();
+    ESP_ERROR_CHECK(esp_netif_set_hostname(s_netif, hostname));   /* DHCP option 12 */
+
+    wifi_init_config_t init = WIFI_INIT_CONFIG_DEFAULT();
+    ESP_ERROR_CHECK(esp_wifi_init(&init));
+    ESP_ERROR_CHECK(esp_event_handler_register(WIFI_EVENT, ESP_EVENT_ANY_ID, &on_wifi, NULL));
+    ESP_ERROR_CHECK(esp_event_handler_register(IP_EVENT, ESP_EVENT_ANY_ID, &on_ip, NULL));
+
+    wifi_config_t cfg = {0};
+    strncpy((char *)cfg.sta.ssid, ssid, sizeof(cfg.sta.ssid) - 1);
+    strncpy((char *)cfg.sta.password, psk, sizeof(cfg.sta.password) - 1);
+    cfg.sta.threshold.authmode = psk[0] ? WIFI_AUTH_WPA2_PSK : WIFI_AUTH_OPEN;
+    cfg.sta.pmf_cfg.capable = true;
+    cfg.sta.pmf_cfg.required = false;
+    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
+    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &cfg));
+    ESP_ERROR_CHECK(esp_wifi_start());
+    ESP_ERROR_CHECK(esp_wifi_set_ps(WIFI_PS_NONE));
+
+    mdns_start(hostname);
+    ESP_LOGI(TAG, "joining %s", ssid);
+}
+
+void wifi_ip(char *buf, size_t n)
+{
+    if (s_connected)
+        snprintf(buf, n, IPSTR, IP2STR(&s_ip));
+    else
+        snprintf(buf, n, "0.0.0.0");
+}
+
+int wifi_rssi(void)
+{
+    wifi_ap_record_t ap;
+    if (!s_connected || esp_wifi_sta_get_ap_info(&ap) != ESP_OK)
+        return 0;
+    return ap.rssi;
+}
+
+bool wifi_connected(void)
+{
+    return s_connected;
+}