diff --git a/hardware/sdcard/diskio.c b/hardware/sdcard/diskio.c
index 2830ffd..c9644a1 100755
--- a/hardware/sdcard/diskio.c
+++ b/hardware/sdcard/diskio.c
@@ -16,12 +16,13 @@
 #include "diskio.h"
 #include "device.h"
 #include "hardware/LED.h"
+#include "util/Config.h"
 
 
 /* Port controls  (Platform dependent) */
 #define CS_LOW()	SD_CS_PORT &= ~(_BV(SD_CS_PIN))			/* CS=low */
 #define	CS_HIGH()	SD_CS_PORT |= _BV(SD_CS_PIN)			/* CS=high */
-#define MMC_CD		((SD_DETECT_INPUT & _BV(SD_DETECT_PIN)))	/* Card detected.   yes:true, no:false, default:true */
+#define MMC_CD		(config_invert_sddetect == false ? (SD_DETECT_INPUT & _BV(SD_DETECT_PIN)) : (SD_DETECT_INPUT & ~_BV(SD_DETECT_PIN)))	/* Card detected.   yes:true, no:false, default:true */
 #define MMC_WP		(false)				/* Write protected. yes:true, no:false, default:false */
 #define	FCLK_SLOW()	SPCR = 0x52		/* Set slow clock (F_CPU / 64) */
 #define	FCLK_FAST()	SPCR = 0x50		/* Set fast clock (F_CPU / 2) */
diff --git a/protocol/KISS.c b/protocol/KISS.c
index 8ecbffe..e7ca52a 100755
--- a/protocol/KISS.c
+++ b/protocol/KISS.c
@@ -613,6 +613,15 @@ void kiss_serialCallback(uint8_t sbyte) {
             if (sbyte == 0x00) {
                 kiss_output_modem_mode();
             }
+        } else if (command == CMD_INVERT_SDDETECT) {
+            if (sbyte == FESC) { ESCAPE = true; } else {
+                if (ESCAPE) {
+                    if (sbyte == TFEND) sbyte = FEND;
+                    if (sbyte == TFESC) sbyte = FESC;
+                    ESCAPE = false;
+                }
+                config_set_invert_sddetect(sbyte);
+            }
         }
     }
 }
diff --git a/protocol/KISS.h b/protocol/KISS.h
index 6b6bb51..e535401 100755
--- a/protocol/KISS.h
+++ b/protocol/KISS.h
@@ -37,6 +37,7 @@
 #define CMD_NMEA 0x40
 #define CMD_PRINT_CONFIG 0xF0
 #define CMD_RETURN 0xFF
+#define CMD_INVERT_SDDETECT 0x15
 
 void kiss_init(AX25Ctx *ax25, Afsk *afsk, Serial *ser);
 void kiss_messageCallback(AX25Ctx *ctx);
diff --git a/util/Config.c b/util/Config.c
index 6bf241b..75b9d53 100644
--- a/util/Config.c
+++ b/util/Config.c
@@ -119,6 +119,7 @@ void config_save_to_eeprom(void) {
 	config_data[i++] = config_gps_mode;
 	config_data[i++] = config_bluetooth_mode;
 	config_data[i++] = config_serial_baudrate;
+	config_data[i++] = config_invert_sddetect;
 
 	md5_hash_t checksum;
 	md5(&checksum, &config_data, config_data_size*8);
@@ -146,6 +147,7 @@ void config_load_defaults(void) {
 	config_bluetooth_mode = CONFIG_BLUETOOTH_AUTODETECT;
 	config_serial_baudrate = CONFIG_BAUDRATE_115200;
 	config_source = CONFIG_SOURCE_DEFAULT;
+	config_invert_sddetect = false;
 }
 
 void config_load_from_eeprom(void) {
@@ -169,6 +171,7 @@ void config_load_from_eeprom(void) {
 	config_gps_mode = config_data[ADDR_E_GPS_MODE];
 	config_bluetooth_mode = config_data[ADDR_E_BLUETOOTH_MODE];
 	config_serial_baudrate = config_data[ADDR_E_SERIAL_BAUDRATE];
+	config_invert_sddetect = config_data[ADDR_E_INVERT_SDDETECT];
 }
 
 bool config_validate_sd(void) {
@@ -243,6 +246,14 @@ void config_set_bt_mode(uint8_t mode) {
 	if (mode == CONFIG_BLUETOOTH_REQUIRED) config_bluetooth_mode = CONFIG_BLUETOOTH_REQUIRED;
 }
 
+void config_set_invert_sddetect(uint8_t invert_sddetect) {
+	if (invert_sddetect == 0x00) {
+		config_invert_sddetect = false;
+	} else {
+		config_invert_sddetect = true;
+	}
+}
+
 void EEPROM_writebyte(uint16_t addr, uint8_t data) {
 	// Disable interrupts
     cli();
diff --git a/util/Config.h b/util/Config.h
index 69732bd..ef2fee8 100644
--- a/util/Config.h
+++ b/util/Config.h
@@ -22,8 +22,9 @@
 #define ADDR_E_GPS_MODE				0x0D
 #define ADDR_E_BLUETOOTH_MODE		0x0E
 #define ADDR_E_SERIAL_BAUDRATE		0x0F
-#define ADDR_E_CHECKSUM				0x10
-#define ADDR_E_END					0x20
+#define ADDR_E_INVERT_SDDETECT		0x10
+#define ADDR_E_CHECKSUM				0x11
+#define ADDR_E_END					0x21
 
 #define CONFIG_GPS_OFF				0x00
 #define CONFIG_GPS_AUTODETECT		0x01
@@ -73,6 +74,7 @@ uint8_t config_gps_mode;
 uint8_t config_gps_nmea_output;
 uint8_t config_bluetooth_mode;
 uint8_t config_serial_baudrate;
+bool config_invert_sddetect;
 
 bool config_user_jobs_enabled;
 bool config_output_diagnostics;
@@ -109,6 +111,7 @@ void config_set_log_packets(uint8_t log_packets);
 void config_set_nmea_output(uint8_t nmea_output);
 void config_set_gps_mode(uint8_t mode);
 void config_set_bt_mode(uint8_t mode);
+void config_set_invert_sddetect(uint8_t inv_sddetect);
 
 void config_enable_diagnostics(void);
 void config_disable_diagnostics(void);