Correct GPIOBase mask width for 32- and 64-pin modules

IO_GPIOBase.h

@@ -124,7 +124,7 @@ bool GPIOBase<T>::_configure(VPIN vpin, ConfigTypeEnum configType, int paramCoun
   #ifdef DIAG_IO
   DIAG(F("%S I2C:%s Config Pin:%d Val:%d"), _deviceName, _I2CAddress.toString(), pin, pullup);
   #endif
-  uint16_t mask = 1 << pin;
+  T mask = T(1) << pin;
   if (pullup) 
     _portPullup |= mask;
   else

test/gpio_base_mask_test.py

@@ -0,0 +1,28 @@
+from pathlib import Path
+import unittest
+
+
+GPIO_BASE = Path(__file__).resolve().parents[1] / "IO_GPIOBase.h"
+
+
+def gpio_pin_mask(width, pin):
+    return (1 << pin) & ((1 << width) - 1)
+
+
+class GPIOBaseMaskTest(unittest.TestCase):
+    def test_production_uses_template_width(self):
+        source = GPIO_BASE.read_text(encoding="utf-8")
+        self.assertIn("T mask = T(1) << pin;", source)
+
+    def test_16_pin_boundary(self):
+        self.assertEqual(gpio_pin_mask(16, 15), 0x8000)
+
+    def test_32_pin_boundary(self):
+        self.assertEqual(gpio_pin_mask(32, 31), 0x80000000)
+
+    def test_64_pin_boundary(self):
+        self.assertEqual(gpio_pin_mask(64, 63), 0x8000000000000000)
+
+
+if __name__ == "__main__":
+    unittest.main()