Reduced GPIO17 (Ethernet clock GPIO) signal strength to reduce noise.

variants/esp32-gateway/variant.cpp

@@ -0,0 +1,36 @@
+/* 
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2024 Olimex Ltd ([email protected])
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "esp32-hal-gpio.h"
+#include "pins_arduino.h"
+#include "driver/gpio.h"
+
+extern "C" {
+// Initialize variant/board, called before setup()
+void initVariant(void)
+{
+// Change the drive strength of the digital output num 17 from the default value 20mA to 5mA
+gpio_set_drive_capability((gpio_num_t)GPIO_NUM_17, GPIO_DRIVE_CAP_0); 
+}
+}