From f38ce1060ca231e4542619d5401e46d22a92c009 Mon Sep 17 00:00:00 2001
From: Scott Shawcroft <scott.shawcroft@gmail.com>
Date: Fri, 1 Jun 2018 13:45:28 -0700
Subject: [PATCH] Support brownout to safe mode. Fixes #870

---
 ports/atmel-samd/supervisor/port.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/ports/atmel-samd/supervisor/port.c b/ports/atmel-samd/supervisor/port.c
index a92ab2913f..63c143c2a8 100644
--- a/ports/atmel-samd/supervisor/port.c
+++ b/ports/atmel-samd/supervisor/port.c
@@ -203,9 +203,16 @@ safe_mode_t port_init(void) {
     }
     #endif
 
-    // if (PM->RCAUSE.bit.BOD33 == 1 || PM->RCAUSE.bit.BOD12 == 1) {
-    //     return BROWNOUT;
-    // }
+    #ifdef SAMD21
+    if (PM->RCAUSE.bit.BOD33 == 1 || PM->RCAUSE.bit.BOD12 == 1) {
+        return BROWNOUT;
+    }
+    #endif
+    #ifdef SAMD51
+    if (RSTC->RCAUSE.bit.BODVDD == 1 || RSTC->RCAUSE.bit.BODCORE == 1) {
+        return BROWNOUT;
+    }
+    #endif
 
     if (board_requests_safe_mode()) {
         return USER_SAFE_MODE;