From 0e513dc79a3e6cfae082ae387d591572de8ab316 Mon Sep 17 00:00:00 2001
From: Travis Shears <t@travisshears.com>
Date: Sun, 22 Feb 2026 11:14:48 +0100
Subject: [PATCH] get pms5003 working

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", readings[reading_i].pm1, readings[reading_i].pm2_5, readings[reading_i].pm10);
", reading_i);
---
 node1.c   | 40 ++++++++++++++++++++++------------------
 pms5003.c | 18 ++++++++++++------
 2 files changed, 34 insertions(+), 24 deletions(-)

diff --git a/node1.c b/node1.c
index 306fd36..f5e0d4f 100644
--- a/node1.c
+++ b/node1.c
@@ -101,6 +101,7 @@ int main() {
 
     if (absolute_time_diff_us(last_sensor_reading, now) >=
         SENSOR_READING_INTERVAL_US) {
+      printf("Sensor reading: %d\n", readings_index);
       last_sensor_reading = now;
       printf("Making BME280 Reading\n");
       current_bem280_reading = bme280_read(&bem_config);
@@ -117,18 +118,21 @@ int main() {
         pms5003_warmup(&pms_config);
       }
 
-      // if (readings_index == 4) {
-      //   printf("Starting reads on PMSS5003\n");
-      //   pms5003_start_reading(&pms_config);
-      // }
+      if (readings_index == 4) {
+        printf("Starting reads on PMSS5003\n");
+        pms5003_start_reading(&pms_config);
+      }
 
-      // if (readings_index == 6) {
-      //   printf("Finished reading PMSS5003\n");
-      //   current_pms5003_reading = pms5003_finish_reading(&pms_config);
-      //   snprintf(msg_to_send, sizeof(msg_to_send), "M02,%.2f,%.2f,%2f\n",
-      //            current_pms5003_reading.pm1, current_pms5003_reading.pm2_5,
-      //            current_pms5003_reading.pm10);
-      // }
+      if (readings_index == 6) {
+        printf("Finished reading PMSS5003\n");
+        current_pms5003_reading = pms5003_finish_reading(&pms_config);
+        snprintf(msg_to_send, sizeof(msg_to_send), "M02,%.2f,%.2f,%2f\n",
+                 current_pms5003_reading.pm1, current_pms5003_reading.pm2_5,
+                 current_pms5003_reading.pm10);
+        printf(
+            "Sending particle matter readings to backend server...\n");
+        send_msg(msg_to_send);
+      }
 
       readings_index++;
       if (readings_index >= 10) {
@@ -142,27 +146,27 @@ int main() {
       // Check connection status
       int link_status = cyw43_tcpip_link_status(&cyw43_state, CYW43_ITF_STA);
 
-      printf("[WiFi Status Check]\n");
-      printf("  Link Status: ");
+      // printf("[WiFi Status Check]\n");
+      // printf("  Link Status: ");
       switch (link_status) {
       case CYW43_LINK_DOWN:
-        printf("DOWN\n");
+        // printf("DOWN\n");
         gpio_put(WIFI_STATUS_LED_PIN, false);
         break;
       case CYW43_LINK_JOIN:
-        printf("JOINING\n");
+        // printf("JOINING\n");
         gpio_put(WIFI_STATUS_LED_PIN, false);
         break;
       case CYW43_LINK_NOIP:
-        printf("NO IP\n");
+        // printf("NO IP\n");
         gpio_put(WIFI_STATUS_LED_PIN, false);
         break;
       case CYW43_LINK_UP:
-        printf("UP\n");
+        // printf("UP\n");
         gpio_put(WIFI_STATUS_LED_PIN, true);
         break;
       default:
-        printf("UNKNOWN (%d)\n", link_status);
+        // printf("UNKNOWN (%d)\n", link_status);
         gpio_put(WIFI_STATUS_LED_PIN, false);
         break;
       }
diff --git a/pms5003.c b/pms5003.c
index f2813b8..c7a9dd5 100644
--- a/pms5003.c
+++ b/pms5003.c
@@ -5,6 +5,7 @@
 #include <hardware/regs/intctrl.h>
 #include <stdint.h>
 #include <stdio.h>
+#include <hardware/watchdog.h>
 
 /**
 Lib for Plantower PMS5003 Particulate Matter (PM) Sensor
@@ -50,6 +51,7 @@ static pms5003_reading extract_pm_values_from_rx_buf() {
 
 static void on_uart_rx() {
   // TODO: make the uart1 dynamic
+  watchdog_update();
   while (read && reading_i < MAX_READINGS && uart_is_readable(uart1)) {
     uint8_t ch = uart_getc(uart1);
     // start of a message
@@ -57,6 +59,13 @@ static void on_uart_rx() {
       printf("pms5003 reading received\n");
       rx_i = 0;
     }
+
+    // Bounds check before accessing array
+    if (rx_i >= 32) {
+      rx_i = 0;
+      continue;
+    }
+
     rx_buf[rx_i] = ch;
     rx_i++;
     // end of message
@@ -65,11 +74,6 @@ static void on_uart_rx() {
       printf("pm1: %f, pm2.5: %f, pm10: %f\n", readings[reading_i].pm1, readings[reading_i].pm2_5, readings[reading_i].pm10);
       reading_i++;
     }
-
-    // guard
-    if (rx_i > 32) {
-      rx_i = 0;
-    }
   }
 }
 
@@ -82,7 +86,7 @@ void pms5003_init(pms5003_config *new_config, uart_inst_t *uart, uint8_t tx_pin,
   uart_set_format(uart, 8, 1, UART_PARITY_NONE);
   irq_set_exclusive_handler(UART1_IRQ, on_uart_rx);
   irq_set_enabled(UART1_IRQ, true);
-  uart_set_irq_enables(uart, true, false);
+  uart_set_irq_enables(uart, false, false);
 
   // high level or suspending is normal working status, while low level is
   // sleeping mode.
@@ -126,11 +130,13 @@ void pms5003_warmup(pms5003_config *config) { gpio_put(config->enable_pin, 1); }
 void pms5003_start_reading(pms5003_config *config) {
   reading_i = 0;
   read = true;
+  uart_set_irq_enables(config->uart, true, false);
 }
 
 pms5003_reading pms5003_finish_reading(pms5003_config *config) {
   printf("readings_i: %d\n", reading_i);
   read = false;
+  uart_set_irq_enables(config->uart, false, false);
   gpio_put(config->enable_pin, 0);
   pms5003_reading average_reading = compute_avarage_reading();
   reading_i = 0;