From: Mark Qvist <mark@unsigned.io>
Date: Sat, 30 Mar 2024 14:11:24 +0000 (+0100)
Subject: Use hardware RNG for CSMA r-value seed on ESP32
X-Git-Url: https://git.tnoah.ca/?a=commitdiff_plain;h=e63b5b6cdbae90ad22448b5ca25a384c3953d533;p=lora-radio.git

Use hardware RNG for CSMA r-value seed on ESP32
---

diff --git a/RNode_Firmware.ino b/RNode_Firmware.ino
index 54ddb12..7b46094 100644
--- a/RNode_Firmware.ino
+++ b/RNode_Firmware.ino
@@ -60,8 +60,17 @@ void setup() {
     }
   #endif
 
-  // Seed the PRNG
-  randomSeed(analogRead(0));
+  // Seed the PRNG for CSMA R-value selection
+  # if MCU_VARIANT == MCU_ESP32
+    // On ESP32, get the seed value from the
+    // hardware RNG
+    int seed_val = (int)esp_random();
+  #else
+    // Otherwise, get a pseudo-random seed
+    // value from an unconnected analog pin
+    int seed_val = analogRead(0);
+  #endif
+  randomSeed(seed_val);
 
   // Initialise serial communication
   memset(serialBuffer, 0, sizeof(serialBuffer));