From e3d83f62ef00f72cd4e802c3c5de5e480eb0dd4e Mon Sep 17 00:00:00 2001
From: GMagician <3684609+GMagician@users.noreply.github.com>
Date: Sat, 15 Apr 2023 11:33:40 +0200
Subject: [PATCH 1/2] Fix M503C

---
 Marlin/src/gcode/eeprom/M500-M504.cpp | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/Marlin/src/gcode/eeprom/M500-M504.cpp b/Marlin/src/gcode/eeprom/M500-M504.cpp
index 6da1d1cbd73b..d63d1fc9a774 100644
--- a/Marlin/src/gcode/eeprom/M500-M504.cpp
+++ b/Marlin/src/gcode/eeprom/M500-M504.cpp
@@ -66,11 +66,20 @@ void GcodeSuite::M502() {
 
     #if ENABLED(CONFIGURATION_EMBEDDING)
       if (parser.seen_test('C')) {
-        SdBaseFile file;
-        const uint16_t size = sizeof(mc_zip);
+        MediaFile file;
+
         // Need to create the config size on the SD card
-        if (file.open(card.getroot(), "mc.zip", O_WRITE|O_CREAT) && file.write(pgm_read_ptr(mc_zip), size) != -1 && file.close())
-          SERIAL_ECHO_MSG("Configuration saved as 'mc.zip'");
+        MediaFile root = card.getroot();
+        if (file.open(&root, "mc.zip", O_WRITE|O_CREAT)) {
+          bool success = true;
+          for (uint16_t i; success && i < sizeof(mc_zip); ++i) {
+            const uint8_t c = pgm_read_byte(&mc_zip[i]);
+            file.write(c);
+          }
+          success = file.close() & success;
+
+          if (success) SERIAL_ECHO_MSG("Configuration saved as 'mc.zip'");
+        }
       }
     #endif
   }

From f1f2dffdf8335e190f19ffb45deec47f5b0351b1 Mon Sep 17 00:00:00 2001
From: GMagician <3684609+GMagician@users.noreply.github.com>
Date: Sat, 15 Apr 2023 11:37:25 +0200
Subject: [PATCH 2/2] Add missing &

---
 Marlin/src/gcode/eeprom/M500-M504.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Marlin/src/gcode/eeprom/M500-M504.cpp b/Marlin/src/gcode/eeprom/M500-M504.cpp
index d63d1fc9a774..a8ffb5fa7d8a 100644
--- a/Marlin/src/gcode/eeprom/M500-M504.cpp
+++ b/Marlin/src/gcode/eeprom/M500-M504.cpp
@@ -76,7 +76,7 @@ void GcodeSuite::M502() {
             const uint8_t c = pgm_read_byte(&mc_zip[i]);
             file.write(c);
           }
-          success = file.close() & success;
+          success = file.close() && success;
 
           if (success) SERIAL_ECHO_MSG("Configuration saved as 'mc.zip'");
         }