From 5f8942c484fd2f6c046de3aab18b618e2c5f2ff3 Mon Sep 17 00:00:00 2001
From: HoLo85 <winter@magic.ms>
Date: Mon, 8 Jun 2020 23:32:25 +0200
Subject: [PATCH 1/4] CMD42 and force erase added

---
 src/SD.cpp              | 12 ++++++
 src/SD.h                |  6 +++
 src/utility/Sd2Card.cpp | 81 +++++++++++++++++++++++++++++++++++++++++
 src/utility/Sd2Card.h   |  3 ++
 src/utility/SdInfo.h    | 10 +++++
 5 files changed, 112 insertions(+)

diff --git a/src/SD.cpp b/src/SD.cpp
index 24fcb2e..45c59eb 100644
--- a/src/SD.cpp
+++ b/src/SD.cpp
@@ -369,6 +369,18 @@ namespace SDLib {
     root.close();
   }
 
+  // protect a card with a password or remove it
+  bool SDClass::lockCard(bool setLock, const char pwd) {
+	  return card.lockCard(setLock, pwd);
+  }
+  
+  // !!CAUTION!! call this to completly erase a card,
+  // this will unlock a card but also delete the complete file system,
+  // reformatting will be required!
+  bool SDClass::forceEraseCard(){
+	  return card.forceEraseCard();
+  }
+
   // this little helper is used to traverse paths
   SdFile SDClass::getParentDir(const char *filepath, int *index) {
     // get parent directory
diff --git a/src/SD.h b/src/SD.h
index c81a7d3..e5896ca 100644
--- a/src/SD.h
+++ b/src/SD.h
@@ -106,6 +106,12 @@ namespace SDLib {
         return rmdir(filepath.c_str());
       }
 
+      // lock card with a password
+      bool lockCard(bool setLock, const char pwd);
+      // !!CAUTION!! this can be used as last resort if the password of a locked card is unknown,
+      // this will remove the files and filesystem, a reformatting of the card is neccessary after this
+	    bool forceEraseCard();
+
     private:
 
       // This is used to determine the mode used to open a file
diff --git a/src/utility/Sd2Card.cpp b/src/utility/Sd2Card.cpp
index 7cfbe73..00fa72c 100644
--- a/src/utility/Sd2Card.cpp
+++ b/src/utility/Sd2Card.cpp
@@ -775,3 +775,84 @@ uint8_t Sd2Card::isBusy(void) {
 
   return (b != 0XFF);
 }
+
+/** Locks a card with a password
+  \param[in] setLock true if the card should be locked, false if it should be unlocked
+  \param[in] pwd password to lock/unlock the card
+  
+	\return true if the locking was successful
+*/
+bool Sd2Card::lockCard(bool setLock, const char *pwd){
+	if(!isBusy()){
+		int16_t i;
+		uint8_t pwd_len = sizeof(pwd);
+		bool locked = false;
+		
+		if(cardCommand(CMD42, 0) != 0){
+			return false;
+		}
+		
+		spiSend(DATA_START_BLOCK);
+		if(setLock) {
+			spiSend(SET_CARD_PWD & 0x07);
+		}
+		else{
+			spiSend(CLEAR_CARD_PWD & 0x07);
+		}
+		
+		spiSend(pwd_len);
+		for(i=0; i<512; i++){
+			if(i<pwd_len){
+				spiSend(pwd[i]);
+			}
+			else{
+				spiSend(0xFF);
+			}
+		}
+		
+		locked = getCardStatus();
+		
+		spiSend(0xFF);
+		spiSend(0xFF);
+		
+		i = 0xFFFF;
+		while(isBusy() && (--i));
+		
+		return locked;
+	}
+}
+
+/** Completly erase a card
+	!! Use with caution !! this removes everything from a card, even the file system.
+	Use this to remove a lock with an unknown password from a card.
+	
+	\return true if the erase was successful
+*/
+bool Sd2Card::forceEraseCard(void) {
+	// set block size to 512 bytes
+	cardCommand(CMD16, 1);
+	
+	// enable 
+	if(cardCommand(CMD42, 0) != 0){
+		return false;
+	}
+	
+	spiSend(DATA_START_BLOCK);
+	spiSend(FORCE_ERASE);
+	
+	return true;
+}
+
+/** Check status of card lock
+
+	\return true if card is locked
+*/
+bool Sd2Card::getCardStatus(void) {
+	bool cardOK = true;
+	
+	if(cardCommand(CMD13, 0) || spiRec()) {
+		cardOK = false;
+	}
+	
+	return cardOK;
+}
diff --git a/src/utility/Sd2Card.h b/src/utility/Sd2Card.h
index 5d91ebf..63fcb8a 100644
--- a/src/utility/Sd2Card.h
+++ b/src/utility/Sd2Card.h
@@ -241,6 +241,9 @@ class Sd2Card {
     uint8_t writeStart(uint32_t blockNumber, uint32_t eraseCount);
     uint8_t writeStop(void);
     uint8_t isBusy(void);
+    bool lockCard(bool setLock, const char *pwd);
+	  bool forceEraseCard(void);
+	  bool getCardStatus(void);
   private:
     uint32_t block_;
     uint8_t chipSelectPin_;
diff --git a/src/utility/SdInfo.h b/src/utility/SdInfo.h
index 6a0e087..d006017 100644
--- a/src/utility/SdInfo.h
+++ b/src/utility/SdInfo.h
@@ -55,6 +55,8 @@ uint8_t const CMD32 = 0X20;
 uint8_t const CMD33 = 0X21;
 /** ERASE - erase all previously selected blocks */
 uint8_t const CMD38 = 0X26;
+/** LOCK_CMD - lock card with password */
+uint8_t const CMD42 = 0x2A; 
 /** APP_CMD - escape for application specific command */
 uint8_t const CMD55 = 0X37;
 /** READ_OCR - read the OCR register of a card */
@@ -82,6 +84,14 @@ uint8_t const WRITE_MULTIPLE_TOKEN = 0XFC;
 uint8_t const DATA_RES_MASK = 0X1F;
 /** write data accepted token */
 uint8_t const DATA_RES_ACCEPTED = 0X05;
+/** mask for setting a card password*/
+uint8_t const SET_CARD_PWD = 0x01;
+/** mask for removing a card password*/
+uint8_t const CLEAR_CARD_PWD = 0x02;
+/** mask for locking or unlocking a card*/
+uint8_t const ACTIVATE_CARD_LOCK = 0x04;
+/** mask to erase the entire card*/
+uint8_t const FORCE_ERASE = 0x08;
 //------------------------------------------------------------------------------
 typedef struct CID {
   // byte 0

From 012482fad33a159e9cfb3a9181d83bd120da79e3 Mon Sep 17 00:00:00 2001
From: HoLo85 <HoLo85@users.noreply.github.com>
Date: Wed, 30 Jul 2025 20:49:46 +0200
Subject: [PATCH 2/4] refactor code

---
 src/SD.h              | 2 +-
 src/utility/Sd2Card.h | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/SD.h b/src/SD.h
index e5896ca..92a5e79 100644
--- a/src/SD.h
+++ b/src/SD.h
@@ -110,7 +110,7 @@ namespace SDLib {
       bool lockCard(bool setLock, const char pwd);
       // !!CAUTION!! this can be used as last resort if the password of a locked card is unknown,
       // this will remove the files and filesystem, a reformatting of the card is neccessary after this
-	    bool forceEraseCard();
+      bool forceEraseCard();
 
     private:
 
diff --git a/src/utility/Sd2Card.h b/src/utility/Sd2Card.h
index 63fcb8a..f5df3e2 100644
--- a/src/utility/Sd2Card.h
+++ b/src/utility/Sd2Card.h
@@ -242,8 +242,8 @@ class Sd2Card {
     uint8_t writeStop(void);
     uint8_t isBusy(void);
     bool lockCard(bool setLock, const char *pwd);
-	  bool forceEraseCard(void);
-	  bool getCardStatus(void);
+    bool forceEraseCard(void);
+    bool getCardStatus(void);
   private:
     uint32_t block_;
     uint8_t chipSelectPin_;

From 056eb385c287982c5afea2bd4c9438a5976f1d04 Mon Sep 17 00:00:00 2001
From: HoLo85 <HoLo85@users.noreply.github.com>
Date: Wed, 30 Jul 2025 21:19:55 +0200
Subject: [PATCH 3/4] add missing CMD16, refactor code

---
 src/SD.cpp              |   4 +-
 src/utility/Sd2Card.cpp | 125 ++++++++++++++++++++--------------------
 src/utility/SdInfo.h    |   2 +
 3 files changed, 66 insertions(+), 65 deletions(-)

diff --git a/src/SD.cpp b/src/SD.cpp
index 960e125..5dbeeab 100644
--- a/src/SD.cpp
+++ b/src/SD.cpp
@@ -373,14 +373,14 @@ namespace SDLib {
 
   // protect a card with a password or remove it
   bool SDClass::lockCard(bool setLock, const char pwd) {
-	  return card.lockCard(setLock, pwd);
+    return card.lockCard(setLock, pwd);
   }
   
   // !!CAUTION!! call this to completly erase a card,
   // this will unlock a card but also delete the complete file system,
   // reformatting will be required!
   bool SDClass::forceEraseCard(){
-	  return card.forceEraseCard();
+    return card.forceEraseCard();
   }
 
   // this little helper is used to traverse paths
diff --git a/src/utility/Sd2Card.cpp b/src/utility/Sd2Card.cpp
index 00fa72c..8f7e021 100644
--- a/src/utility/Sd2Card.cpp
+++ b/src/utility/Sd2Card.cpp
@@ -780,79 +780,78 @@ uint8_t Sd2Card::isBusy(void) {
   \param[in] setLock true if the card should be locked, false if it should be unlocked
   \param[in] pwd password to lock/unlock the card
   
-	\return true if the locking was successful
+  \return true if the locking was successful
 */
 bool Sd2Card::lockCard(bool setLock, const char *pwd){
-	if(!isBusy()){
-		int16_t i;
-		uint8_t pwd_len = sizeof(pwd);
-		bool locked = false;
-		
-		if(cardCommand(CMD42, 0) != 0){
-			return false;
-		}
-		
-		spiSend(DATA_START_BLOCK);
-		if(setLock) {
-			spiSend(SET_CARD_PWD & 0x07);
-		}
-		else{
-			spiSend(CLEAR_CARD_PWD & 0x07);
-		}
-		
-		spiSend(pwd_len);
-		for(i=0; i<512; i++){
-			if(i<pwd_len){
-				spiSend(pwd[i]);
-			}
-			else{
-				spiSend(0xFF);
-			}
-		}
-		
-		locked = getCardStatus();
-		
-		spiSend(0xFF);
-		spiSend(0xFF);
-		
-		i = 0xFFFF;
-		while(isBusy() && (--i));
-		
-		return locked;
-	}
+  if(!isBusy()){
+    int16_t i;
+    uint8_t pwd_len = sizeof(pwd);
+    bool locked = false;
+
+    if(cardCommand(CMD42, 0) != 0){
+      return false;
+    }
+
+    spiSend(DATA_START_BLOCK);
+    if(setLock) {
+      spiSend(SET_CARD_PWD & 0x07);
+    }
+    else{
+      spiSend(CLEAR_CARD_PWD & 0x07);
+    }
+
+    spiSend(pwd_len);
+    for(i=0; i<512; i++){
+      if(i<pwd_len){
+        spiSend(pwd[i]);
+      }
+      else{
+        spiSend(0xFF);
+      }
+    }
+
+    locked = getCardStatus();
+      
+    spiSend(0xFF);
+    spiSend(0xFF);
+
+    i = 0xFFFF;
+    while(isBusy() && (--i));
+
+    return locked;
+  }
 }
 
 /** Completly erase a card
-	!! Use with caution !! this removes everything from a card, even the file system.
-	Use this to remove a lock with an unknown password from a card.
-	
-	\return true if the erase was successful
+  !! Use with caution !! this removes everything from a card, even the file system.
+  Use this to remove a lock with an unknown password from a card.
+
+  \return true if the erase was successful
 */
 bool Sd2Card::forceEraseCard(void) {
-	// set block size to 512 bytes
-	cardCommand(CMD16, 1);
-	
-	// enable 
-	if(cardCommand(CMD42, 0) != 0){
-		return false;
-	}
-	
-	spiSend(DATA_START_BLOCK);
-	spiSend(FORCE_ERASE);
-	
-	return true;
+  // set block size to 512 bytes
+  cardCommand(CMD16, 1);
+
+  // enable 
+  if(cardCommand(CMD42, 0) != 0){
+    return false;
+  }
+
+  spiSend(DATA_START_BLOCK);
+  spiSend(FORCE_ERASE);
+
+  return true;
 }
 
 /** Check status of card lock
-
-	\return true if card is locked
+  \return true if card is locked
 */
 bool Sd2Card::getCardStatus(void) {
-	bool cardOK = true;
-	
-	if(cardCommand(CMD13, 0) || spiRec()) {
-		cardOK = false;
-	}
-	
-	return cardOK;
+  bool cardOK = true;
+
+  if(cardCommand(CMD13, 0) || spiRec()) {
+    cardOK = false;
+  }
+
+  return cardOK;
 }
diff --git a/src/utility/SdInfo.h b/src/utility/SdInfo.h
index d006017..e63e737 100644
--- a/src/utility/SdInfo.h
+++ b/src/utility/SdInfo.h
@@ -42,6 +42,8 @@ uint8_t const CMD9 = 0X09;
 uint8_t const CMD10 = 0X0A;
 /** SEND_STATUS - read the card status register */
 uint8_t const CMD13 = 0X0D;
+/** SET_BLOCKLEN - change r/w block size */
+uint8_t const CMD16 = 0X10;
 /** READ_BLOCK - read a single data block from the card */
 uint8_t const CMD17 = 0X11;
 /** WRITE_BLOCK - write a single data block to the card */

From 37bd9635caf340ad2d9048de3af63476d47e8128 Mon Sep 17 00:00:00 2001
From: HoLo85 <HoLo85@users.noreply.github.com>
Date: Wed, 30 Jul 2025 21:23:39 +0200
Subject: [PATCH 4/4] fix typos

---
 src/SD.cpp              | 2 +-
 src/SD.h                | 2 +-
 src/utility/Sd2Card.cpp | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/SD.cpp b/src/SD.cpp
index 5dbeeab..a952a63 100644
--- a/src/SD.cpp
+++ b/src/SD.cpp
@@ -376,7 +376,7 @@ namespace SDLib {
     return card.lockCard(setLock, pwd);
   }
   
-  // !!CAUTION!! call this to completly erase a card,
+  // !!CAUTION!! call this to completely erase a card,
   // this will unlock a card but also delete the complete file system,
   // reformatting will be required!
   bool SDClass::forceEraseCard(){
diff --git a/src/SD.h b/src/SD.h
index 92a5e79..b1011a5 100644
--- a/src/SD.h
+++ b/src/SD.h
@@ -109,7 +109,7 @@ namespace SDLib {
       // lock card with a password
       bool lockCard(bool setLock, const char pwd);
       // !!CAUTION!! this can be used as last resort if the password of a locked card is unknown,
-      // this will remove the files and filesystem, a reformatting of the card is neccessary after this
+      // this will remove the files and filesystem, a reformatting of the card is necessary after this
       bool forceEraseCard();
 
     private:
diff --git a/src/utility/Sd2Card.cpp b/src/utility/Sd2Card.cpp
index 8f7e021..6ed26cd 100644
--- a/src/utility/Sd2Card.cpp
+++ b/src/utility/Sd2Card.cpp
@@ -822,7 +822,7 @@ bool Sd2Card::lockCard(bool setLock, const char *pwd){
   }
 }
 
-/** Completly erase a card
+/** Completely erase a card
   !! Use with caution !! this removes everything from a card, even the file system.
   Use this to remove a lock with an unknown password from a card.