X-Git-Url: http://git.linex4red.de/pub/lufa.git/blobdiff_plain/6da1677bc33608eddb87b65b86dfc5881dd6c6e8..d5d9ff73e5216969aaa2915de3fa04f530ffe400:/Bootloaders/Incomplete/MassStorage/Lib/VirtualFAT.c

diff --git a/Bootloaders/Incomplete/MassStorage/Lib/VirtualFAT.c b/Bootloaders/Incomplete/MassStorage/Lib/VirtualFAT.c
index 7a248d87e..24df348f0 100644
--- a/Bootloaders/Incomplete/MassStorage/Lib/VirtualFAT.c
+++ b/Bootloaders/Incomplete/MassStorage/Lib/VirtualFAT.c
@@ -42,15 +42,15 @@ static const FATBootBlock_t BootBlock =
 		.TotalSectors16          = LUN_MEDIA_BLOCKS,
 		.MediaDescriptor         = 0xF8,
 		.SectorsPerFAT           = 1,
-		.SectorsPerTrack         = 32,
-		.Heads                   = 64,
+		.SectorsPerTrack         = LUN_MEDIA_BLOCKS % 64,
+		.Heads                   = LUN_MEDIA_BLOCKS / 64,
 		.HiddenSectors           = 0,
 		.TotalSectors32          = 0,
 		.PhysicalDriveNum        = 0,
 		.ExtendedBootRecordSig   = 0x29,
 		.VolumeSerialNumber      = 0x12345678,
 		.VolumeLabel             = "LUFA BOOT  ",
-		.FilesystemIdentifier    = "FAT16   ",
+		.FilesystemIdentifier    = "FAT12   ",
 		.BootstrapProgram        = {0},
 		.MagicSignature          = 0xAA55,
 	};
@@ -64,11 +64,33 @@ static FATDirectoryEntry_t FirmwareFileEntry =
 		.CreationTime    = FAT_TIME(1, 1, 0),
 		.CreationDate    = FAT_DATE(14, 2, 1989),
 		.StartingCluster = 2,
-		.FileSizeBytes   = 2049,
+		.FileSizeBytes   = FIRMWARE_FILE_SIZE,
 	};
 
 
-static void WriteBlock(uint16_t BlockNumber)
+static void UpdateFAT12ClusterEntry(uint8_t* FATTable,
+                                    const uint16_t Index,
+                                    const uint16_t ChainEntry)
+{
+	/* Calculate the starting offset of the cluster entry in the FAT12 table */
+	uint8_t FATOffset   =   (Index * 3) / 2;
+	bool    UpperNibble = (((Index * 3) % 2) != 0);
+
+	/* Check if the start of the entry is at an upper nibble of the byte, fill
+	 * out FAT12 entry as required */
+	if (UpperNibble)
+	{
+		FATTable[FATOffset]     = (FATTable[FATOffset] & 0x0F) | ((ChainEntry & 0x0F) << 4);
+		FATTable[FATOffset + 1] = (ChainEntry >> 4);
+	}
+	else
+	{
+		FATTable[FATOffset]     = ChainEntry;
+		FATTable[FATOffset + 1] = (FATTable[FATOffset] & 0xF0) | (ChainEntry >> 8);
+	}
+}
+
+static void WriteBlock(const uint16_t BlockNumber)
 {
 	uint8_t BlockBuffer[512];
 
@@ -79,56 +101,45 @@ static void WriteBlock(uint16_t BlockNumber)
 	Endpoint_Read_Stream_LE(BlockBuffer, sizeof(BlockBuffer), NULL);
 	Endpoint_ClearOUT();
 
-	printf("WRITE %d\r\n", BlockNumber);
 	// TODO: Write to FLASH
 }
 
-static void ReadBlock(uint16_t BlockNumber)
+static void ReadBlock(const uint16_t BlockNumber)
 {
 	uint8_t BlockBuffer[512];
 	memset(BlockBuffer, 0x00, sizeof(BlockBuffer));
 
-	printf("READ %d", BlockNumber);
-
 	switch (BlockNumber)
 	{
 		case 0:
 			memcpy(BlockBuffer, &BootBlock, sizeof(FATBootBlock_t));
-			printf(" <B>\r\n");
 			break;
 
 		case 1:
 		case 2:
-			printf(" <F>\r\n");
-
 			/* Cluster 0: Media type/Reserved */
-			((uint16_t*)&BlockBuffer)[0] = 0xFF00 | BootBlock.MediaDescriptor;
+			UpdateFAT12ClusterEntry(BlockBuffer, 0, 0xF00 | BootBlock.MediaDescriptor);
 
 			/* Cluster 1: Reserved */
-			((uint16_t*)&BlockBuffer)[1] = 0xFFFF;
+			UpdateFAT12ClusterEntry(BlockBuffer, 1, 0xFFF);
 
 			/* Cluster 2 onwards: Cluster chain of FIRMWARE.BIN */
-			for (uint16_t i = 0; i < FILE_CLUSTERS(2049); i++)
-			{
-				((uint16_t*)&BlockBuffer)[i + 2] = i + 3;
-			}
+			for (uint16_t i = 0; i < FILE_CLUSTERS(FIRMWARE_FILE_SIZE); i++)
+			  UpdateFAT12ClusterEntry(BlockBuffer, i+2, i+3);
 
 			/* Mark last cluster as end of file */
-			((uint16_t*)&BlockBuffer)[FILE_CLUSTERS(2049) + 1] = 0xFFFF;
+			UpdateFAT12ClusterEntry(BlockBuffer, FILE_CLUSTERS(FIRMWARE_FILE_SIZE) + 1, 0xFFF);
 			break;
 
 		case 3:
-			printf("<R>\r\n");
 			memcpy(BlockBuffer, &FirmwareFileEntry, sizeof(FATDirectoryEntry_t));
 			break;
 
 		default:
-			if ((BlockNumber >= 4) && (BlockNumber < (4 + FILE_CLUSTERS(FIRMWARE_FILE_SIZE))))
+			if ((BlockNumber >= 4) && (BlockNumber < (4 + (FIRMWARE_FILE_SIZE / SECTOR_SIZE_BYTES))))
 			{
-				printf("<D>\r\n");
-
 				for (uint16_t i = 0; i < 512; i++)
-				  BlockBuffer[i] = '0' + BlockNumber; //A' + (i % 26);
+				  BlockBuffer[i] = 'A' + (i % 26);
 			}
 
 			break;