Patch file for meshtastic firmware to support a lifepo4 battery and sense the voltage on it using a voltage divider. Patch created on tag `v2.4.2.5b45303` of meshtastic firmware.

meshtastic-rp2040-lora-batt-sns.patch

diff --git a/platformio.ini b/platformio.ini
index e60f0d7b..dba29771 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -2,8 +2,9 @@
 ; https://docs.platformio.org/page/projectconf.html
 
 [platformio]
-default_envs = tbeam
-;default_envs = pico
+default_envs = rp2040-lora
+; default_envs = tbeam
+; default_envs = pico
 ;default_envs = tbeam-s3-core
 ;default_envs = tbeam0.7
 ;default_envs = heltec-v1
@@ -153,6 +154,6 @@ lib_deps =
   https://github.com/KodinLanewave/INA3221@^1.0.0
   lewisxhe/SensorLib@^0.2.0
   mprograms/QMC5883LCompass@^1.2.0
-  
+
 
   https://github.com/meshtastic/DFRobot_LarkWeatherStation#dee914270dc7cb3e43fbf034edd85a63a16a12ee
diff --git a/variants/rp2040-lora/variant.h b/variants/rp2040-lora/variant.h
index 1f42c4db..bbcee556 100644
--- a/variants/rp2040-lora/variant.h
+++ b/variants/rp2040-lora/variant.h
@@ -19,10 +19,11 @@
 
 #define LED_PIN PIN_LED
 
-// #define BATTERY_PIN 26
-//  ratio of voltage divider = 3.0 (R17=200k, R18=100k)
-// #define ADC_MULTIPLIER 3.1 // 3.0 + a bit for being optimistic
-
+#define BATTERY_PIN 27
+//  ratio of voltage divider = 3.0 (R1=R2=47K)
+#define ADC_MULTIPLIER 2.1 // 3.0 + a bit for being optimistic
+#define BATTERY_SENSE_RESOLUTION_BITS ADC_RESOLUTION
+#define CELL_TYPE_LIFEPO4
 #define USE_SX1262
 
 #undef LORA_SCK