# HG changeset patch
# User ideenmodellierer
# Date 1581796220 -3600
# Node ID 86fcac4cc43a6baaac2602862b250d371f27bc55
# Parent  2b31cf1ebbcc61092467434f8b950b751d279ea9
Added function to analyse the sampel ringbuffer:
The function will show 0 for used sectors, 4 for the sector currently in use and 5 for empty sectors. This allows identification of log sample index position and identification of a buffer corruption (more than 2 sectors have state 4)
The repair function writes dummy bytes to the end of the active buffer with the lower sector number. This decision is based on the fact that corruption results typically in a reset of index to buffer start address. After repair the writing will be continued using the hugher buffer marked as used.

diff -r 2b31cf1ebbcc -r 86fcac4cc43a Discovery/Inc/externLogbookFlash.h
--- a/Discovery/Inc/externLogbookFlash.h	Sat Feb 15 20:45:19 2020 +0100
+++ b/Discovery/Inc/externLogbookFlash.h	Sat Feb 15 20:50:20 2020 +0100
@@ -59,18 +59,18 @@
  */
 #define SETTINGSSTART	0x00010000
 #define SETTINGSSTOP 	0x0001FFFF
-#define VPMSTART			0x00020000
-#define VPMSTOP				0x0002FFFF
+#define VPMSTART		0x00020000
+#define VPMSTOP			0x0002FFFF
 #define unused3START	0x00030000
 #define unused3STOP		0x0007FFFF
 #define HEADERSTART		0x00080000
 #define HEADERSTOP		0x000FFFFF
 #define SAMPLESTART		0x00100000
 #define SAMPLESTOP		0x00CFFFFF
-#define FWSTART				0x00D00000
-#define FWSTOP				0x00DFFFFF
-#define FWSTART2			0x00E00000
-#define FWSTOP2				0x00FFFFFF
+#define FWSTART			0x00D00000
+#define FWSTOP			0x00DFFFFF
+#define FWSTART2		0x00E00000
+#define FWSTOP2			0x00FFFFFF
 /* 16 MB with 4 Byte addressing */
 #define unused4START	0x01000000
 #define unused4STOP		0x01FFFFFF
@@ -78,6 +78,12 @@
 #define HEADERSIZE sizeof(SLogbookHeader)
 #define HEADERSIZEOSTC3 sizeof(SLogbookHeaderOSTC3)
 
+/* Sample ring buffer sector states derived from the usage at begin and end of a sector */
+#define SECTOR_CLOSED		(0)
+#define SECTOR_NOTUSED		(1)
+#define SECTOR_INUSE		(4)
+#define SECTOR_EMPTY		(5)
+
 /* Exported types ------------------------------------------------------------*/
 typedef struct{
 uint8_t byteLow;
@@ -157,4 +163,7 @@
 
 uint16_t ext_flash_repair_SPECIAL_dive_numbers_starting_count_with(uint16_t startCount);
 
+uint32_t ext_flash_AnalyseSampleBuffer(char *pstrResult);
+void ext_flash_CloseSector(void);
+
 #endif /* EXTERN_LOGBOOK_FLASH_H */
diff -r 2b31cf1ebbcc -r 86fcac4cc43a Discovery/Src/externLogbookFlash.c
--- a/Discovery/Src/externLogbookFlash.c	Sat Feb 15 20:45:19 2020 +0100
+++ b/Discovery/Src/externLogbookFlash.c	Sat Feb 15 20:50:20 2020 +0100
@@ -117,6 +117,7 @@
 /* Private variables ---------------------------------------------------------*/
 static uint32_t	actualAddress = 0;
 static uint32_t	preparedPageAddress = 0;
+static uint32_t closeSectorAddress = 0;
 static uint32_t	entryPoint = 0;
 
 static uint32_t	actualPointerHeader = 0;
@@ -1362,16 +1363,16 @@
     ext_flash_read_block(&dataStart.u8bit.byteMidLow, EF_HEADER);
     ext_flash_read_block(&dataStart.u8bit.byteMidHigh, EF_HEADER);
     ext_flash_read_block_stop();
-    if((header1 == 0xFA) && (header2 == 0xFA))
+    if((header1 == 0xFA) && (header2 == 0xFA))						/* Header is indicating the start of a dive */
     {
       actualAddress = HEADERSTART + (0x800 * id) + HEADER2OFFSET;
       ext_flash_read_block_start();
       ext_flash_read_block(&header1, EF_HEADER);
       ext_flash_read_block(&header2, EF_HEADER);
       ext_flash_read_block_stop();
-      if((header1 != 0xFA) || (header2 != 0xFA))
+      if((header1 != 0xFA) || (header2 != 0xFA))					/* Secondary header was not written at the end of a dive */
       {
-        actualPointerSample = dataStart.u32bit;
+        actualPointerSample = dataStart.u32bit;						/* Set datapointer to position stored in header written at beginning of dive */
         actualAddress = actualPointerSample;
         logbook_recover_brokenlog(id);
         SSettings *settings = settingsGetPointer();
@@ -2097,6 +2098,131 @@
   {
   }
 }
+
+void ext_flash_CloseSector(void)
+{
+	uint32_t actualAddressBackup = actualAddress;
+	int i=0;
+
+	if(closeSectorAddress != 0)
+	{
+	/* write some dummy bytes to the sector which is currently used for storing samples. This is done to "hide" problem if function is calles again */
+		actualAddress = closeSectorAddress;
+
+		wait_chip_not_busy();
+		write_spi(0x06,RELEASE);		/* WREN */
+		write_spi(0x02,HOLDCS);			/* write cmd */
+		write_address(HOLDCS);
+		for(i = 0; i<8; i++)
+		{
+			write_spi(0xA5,HOLDCS);/* write data */
+			actualAddress++;
+		}
+		/* byte with RELEASE */
+		write_spi(0xA5,RELEASE);/* write data */
+		actualAddress = actualAddressBackup;
+		closeSectorAddress = 0;
+	}
+}
+
+uint32_t ext_flash_AnalyseSampleBuffer(char *pstrResult)
+{
+	uint8_t sectorState[16];	/* samples are stored in 16 sector / 64k each */
+	uint32_t curAddress = SAMPLESTART;
+	uint8_t curSector = 0;
+	uint8_t samplebuffer[10];
+	uint32_t actualAddressBackup = actualAddress;
+	uint8_t emptyCellCnt = 0;
+	uint32_t i = 0;
+	uint8_t startedSectors = 0;
+	uint8_t	lastSectorInuse = 0;
+
+/* check if a sector is used till its end */
+	for(curSector = 0; curSector < 16; curSector++)
+	{
+		sectorState[curSector] = 0;
+		emptyCellCnt = 0;
+		curAddress = SAMPLESTART + (curSector * 0x10000);	/* set address to begin of sector and check if it is used */
+		actualAddress = curAddress;
+		ext_flash_read_block_start();
+		for(uint32_t i=0;i<10;i++)
+		{
+			samplebuffer[i] = read_spi(HOLDCS);/* read data */
+			if(samplebuffer[i] == 0xFF)
+			{
+				emptyCellCnt++;
+			}
+		}
+		ext_flash_read_block_stop();
+		if(emptyCellCnt == 10)
+		{
+			sectorState[curSector] = SECTOR_NOTUSED;
+		}
+		emptyCellCnt = 0;
+		curAddress = SAMPLESTART + (curSector * 0x10000) + 0xFFF5;	/* set address to end of sector and check if it is used */
+		actualAddress = curAddress;
+		ext_flash_read_block_start();
+		for(i=0;i<10;i++)
+		{
+			samplebuffer[i] = read_spi(HOLDCS);/* read data */
+			if(samplebuffer[i] == 0xFF)
+			{
+				emptyCellCnt++;
+			}
+		}
+		ext_flash_read_block_stop();
+		if(emptyCellCnt == 10)
+		{
+			sectorState[curSector] |= SECTOR_INUSE;		/* will become SECTOR_EMPTY if start is NOTUSED */
+		}
+	}
+
+	for(i=0;i<16;i++)
+	{
+		if( sectorState[i] == SECTOR_INUSE)
+		{
+			startedSectors++;
+			lastSectorInuse = i;
+		}
+		*(pstrResult+i) = sectorState[i] + 48;
+	}
+
+	if(startedSectors > 1)	/* more than one sector is in used => ring buffer corrupted */
+	{
+		if(startedSectors == 2)			/* only fix issue if only two sectors are in used. Otherwise fixing will cause more worries than help */
+		{
+		/* the logic behind healing of the problem is that the larger address is the oldest one => restore the largest address */
+			curAddress = SAMPLESTART + (lastSectorInuse * 0x10000);
+			emptyCellCnt = 0;
+			actualAddress = curAddress;
+			ext_flash_read_block_start();
+			while((emptyCellCnt < 10) && (actualAddress < curAddress + 0x10000))
+			{
+				samplebuffer[0] = read_spi(HOLDCS);/* read data */
+				if(samplebuffer[0] == 0xFF)
+				{
+					emptyCellCnt++;
+				}
+				else
+				{
+					emptyCellCnt = 0;
+				}
+				actualAddress++;
+			}
+			ext_flash_read_block_stop();
+			actualAddress -= 10;	/* step 10 bytes back to the start of free bytes */
+			actualPointerSample = actualAddress;
+
+			closeSectorAddress = settingsGetPointer()->logFlashNextSampleStartAddress & 0xFFFF0000;
+			closeSectorAddress += 0xFFF5; /* to be used once next time a dive is logged. Needed because NextSampleID is derived at every startup */
+			settingsGetPointer()->logFlashNextSampleStartAddress = actualPointerSample;	/* store new position to be used for next dive */
+		}
+	}
+	actualAddress = actualAddressBackup;
+	*(pstrResult+i) = 0;
+	return startedSectors;
+}
+
 /*
 uint8_t ext_flash_erase_firmware_if_not_empty(void)
 {