From 110bd494072684638a3d512b325d72aeeab9592c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jo=C3=A3o=20Br=C3=A1zio?= <jbrazio@gmail.com>
Date: Mon, 16 Jun 2025 19:51:53 +0100
Subject: [PATCH] VBAT schematic

---
 src/helpers/rp2040/WaveshareBoard.cpp |  3 ++-
 src/helpers/rp2040/WaveshareBoard.h   | 18 ++++++++++++++----
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/src/helpers/rp2040/WaveshareBoard.cpp b/src/helpers/rp2040/WaveshareBoard.cpp
index 12e3d4f1..2e622933 100644
--- a/src/helpers/rp2040/WaveshareBoard.cpp
+++ b/src/helpers/rp2040/WaveshareBoard.cpp
@@ -16,7 +16,8 @@ void WaveshareBoard::begin() {
 #endif
 
 #if defined(PIN_BOARD_SDA) && defined(PIN_BOARD_SCL)
-  Wire.setPins(PIN_BOARD_SDA, PIN_BOARD_SCL);
+  Wire.setSDA(PIN_BOARD_SDA);
+  Wire.setSCL(PIN_BOARD_SCL);
 #endif
 
   Wire.begin();
diff --git a/src/helpers/rp2040/WaveshareBoard.h b/src/helpers/rp2040/WaveshareBoard.h
index 492d54df..a09c4b62 100644
--- a/src/helpers/rp2040/WaveshareBoard.h
+++ b/src/helpers/rp2040/WaveshareBoard.h
@@ -18,10 +18,20 @@
 #define SX126X_DIO2_AS_RF_SWITCH true
 #define SX126X_DIO3_TCXO_VOLTAGE 0
 
-// This board has no built-in way to read battery voltage
-// #define PIN_VBAT_READ    26
-// #define BATTERY_SAMPLES  8
-// #define ADC_MULTIPLIER   (3.1 * 3.3 * 1000) // MT Uses 3.1
+/*
+ * This board has no built-in way to read battery voltage.
+ * Nevertheless it's very easy to make it work, you only require two 1% resistors.
+ *
+ *    VSYS -- /\/\/\/\-- --+
+ *              200k       |
+ *                         +-- GPIO28
+ *                         |
+ *     GND -- /\/\/\/\-- --+
+ *              100k
+ */
+#define PIN_VBAT_READ            28
+#define BATTERY_SAMPLES          8
+#define ADC_MULTIPLIER           (3.0f * 3.3f * 1000)
 
 class WaveshareBoard : public mesh::MainBoard {
 protected: