1 files changed, 2 insertions, 2 deletions
diff --git a/src/samd21/serial.c b/src/samd21/serial.c
index 3c321e47..895ffb27 100644
--- a/src/samd21/serial.c
+++ b/src/samd21/serial.c
@@ -16,8 +16,8 @@ serial_init(void)
     // Enable serial clock
     enable_pclock(SERCOM0_GCLK_ID_CORE, PM_APBCMASK_SERCOM0);
     // Enable pins
-    gpio_peripheral('A', 10, 'C', 0);
-    gpio_peripheral('A', 11, 'C', 0);
+    gpio_peripheral(GPIO('A', 10), 'C', 0);
+    gpio_peripheral(GPIO('A', 11), 'C', 0);
     // Configure serial
     SercomUsart *su = &SERCOM0->USART;
     su->CTRLA.reg = 0;