Окружение AVR-DOS

Окружение AVR-DOS — конфигурация системы

AVR-DOS применительно к на данному микроконтроллеру.

Конфигурация файловой системы

Задается файлом config_avr-dos.bas.

Параметр	Значение
cFileHandles	Count of Filehandles: for each file opened at same time, a filehandle buffer of 538 Bytes is needed
cSepFATHandle	For higher speed in handling file operations the FAT info can be stored in an own buffer, which needs additional 517 Bytes. Assign Constant cSepFATHandle with 1, if wanted, otherwise with 0.
cFATDirSaveAtEnd	Handling of saving changed FAT and Directory Information of a open file for output. Parameter 0 saves FAT and Directory information with every saving of a data sector Parameter 1 saves FAT and Directory Information only at the CLOSE and FLUSH statement. This option increases the writing speed of data and decreases the write frequency of FAT and Directory Sectors
cTextQuotationMarks	Surrounding String with Quotation Marks at the Command WRITE 0 = No Surrounding of strings with quotation.marks 1 = Surrounding of strings with quotation.marks (f.E. "Text")
cFATSecondUpdate	Suppress updating of second FAT. Windows accepts a not updated second FAT PC-Command: chkdsk /f corrects the second FAT, it overwrites the second FAT with the first FAT set this parameter to 0 for high speed continuing saving data 0 = Second FAT is not updated 1 = Second FAT is updated if exist [default]
cVariableSeparator	Character to separate ASCII Values in WRITE - statement (and INPUT) Normally a comma (,) is used, but it can be changed to other values, f.E. to TAB (ASCII-Code 9) if EXCEL Files with Tab separated values should be written or read. This parameter works for WRITE and INPUT Parameter value is the ASSCII-Code of the separator 44 = comma [default] 9 = TAB

Использование памяти файловой системой

General File System information (35 Bytes)

Параметр	Тип	Использование
gbDOSError	Byte	holds DOS Error of last file handling routine
gbFileSystem	Byte	File System Code from Master Boot Record
gbFileSystemStatus	Byte	Holds Information about FAT Type (16 or 32)
glFATFirstSector	Long	Number of first Sector of FAT Area on the Card
gbNumberOfFATs	Byte	Count of FAT copies
glSectorsPerFat	Long	Count of Sectors per FAT
glRootFirstSector	Long	Number of first Sector of Root Area on the Card
gwRootEntries	Word	Count of Root Entries
glDataFirstSector	Long	Number of first Sector of Data Area on the Card
gbSectorsPerCluster	Byte	Count of Sectors per Cluster
glMaxClusterNumber	Long	Highest usable Cluster number
glLastSearchedCluster	Long	Last cluster number found as free
glFS_Temp1	Long	temorary Long variable for file system

Directory (559 Bytes)

Параметр	Тип	Использование
glDirFirstSectorNumber	Long	Number of first sector of current actual directory
gwFreeDirEntry	Word	Number of first free Dir-Entry
glFreeDirSectorNumber	Long	Number of Sector number with first free Directory Entry
gsDir0TempFileName	String*11	Temporary Buffer for file name
gwDir0Entry	Word	Temporary Buffer for Directory Entry Number
glDir0SectorNumber	Long	Temporary Buffer for Directory Sector Number
gsTempFileName	String*11	Hold file name for directory search
gwDirRootEntry	Word	Number of last handled directory entry
glDirSectorNumber	Long	Number of current loaded Sector
gbDirBufferStatus	Byte	Sector Buffer Status
gbDirBuffer	Byte (512)	Buffer for directory Sector

FAT (517 Bytes)

FAT Buffer is only allocated if the constant: cSepFATHandle = 1

Параметр	Тип	Использование
glFATSectorNumber	Long	Number of current loaded FAT sector
gbFATBufferStatus	Byte	Buffer status
gbFATBuffer	Byte(512)	buffer for FAT sector

File handling

Each file handle has a block of 538 Bytes in the variable abFileHandle which is a byte-array of size (538 * cFileHandles)

Параметр	Тип	Использование
FileNumber	Byte	File number for identification of the file in I/O operations to the opened file
FileMode	Byte	File open mode
FileDirEntry	Word	Number of directory entry
FileDirSectorNumber	Long	Number of Sector which holds the Directory entry of the file
FileFirstCluster	Word	First cluster
FileSize	Long	file size in bytes
FilePosition	Long	file pointer (next read/write) 0-based
FileSectorNumber	Long	number of current loaded sector
FileBufferStatus	Byte	buffer Status
FileBuffer	Byte(512)	buffer for the file sector
SectorTerminator	Byte	additional 00 Byte (string terminator) for direct reading ASCII files from the buffer

Error codes

Код	Имя в компиляторе	Объяснение
0	cpNoError	No Error
1	cpEndOfFile	Attempt behind End of File
17	cpNoMBR	Sector 0 on Card is not a Master Boot Record
18	cpNoPBR	No Partition Sector
19	cpFileSystemNotSupported	Only FAT16 File system is supported
20	cpSectorSizeNotSupported	Only sector size of 512 Bytes is supported
21	cpSectorsPerClusterNotSupported	which are not power of 2 are not supported
22	cpCountOfClustersNotSupported	Count of FAT (valid is 1 or 2) not supported (will be renamed with one of next release)
33	cpNoNextCluster	Error in file cluster chain
34	cpNoFreeCluster	No free cluster to allocate (Disk full)
35	cpClusterError	Error in file cluster chain
49	cpNoFreeDirEntry	Directory full
50	cpFileExist
51	cpFileDeleteNotAllowed	Deleting of file not allowed (System, Hidden, Read-Only)
52	cpSubDirectoryNotEmpty	Removing of sub-directory not possible, because it is not empty
53	cpSubDirectoryError	General error at handling with sub-directory
54	cpNoASubDirectory	Passed name is a file name and not a directory name
65	cpNoFreeFileNumber	No free file number available, only theoretical error, if 255 file handles in use
66	cpFileNotFound	File not found
67	cpFileNumberNotFound	No file handle with such file number
68	cpFileOpenNoHandle	All file handles occupied
69	cpFileOpenHandleInUse	File handle number in use, can't create a new file handle with same file number
70	cpFileOpenShareConflict	Tried to open a file in read and write modus in two file handles
71	cpFileInUse	Can't delete file, which is in use
72	cpFileReadOnly	Can't open a read only file for writing
73	cpFileNoWildCardAllowed	No wildcard allowed in this function
74	CpFileNumberInvalid	File number 0 is not allowed
97	cpFilePositionError
98	cpFileAccessError	function not allowed in this file open mode
99	cpInvalidFilePosition	new file position pointe is invalid (minus or 0)
100	cpFileSizeToGreat	File size to great for function BLoad

Buffer Status: Bit definitions of Buffer Status Byte (Directory, FAT and File)

Bit	DIR	FAT	File	Compiler Alias	Remark
0 (LSB)			+	dFATDirSaveAnyWay	Status Bit which is set from CLOSE and FLUSh statement, to show AVR-DOS to save FAT and Directory Sectors
1			+	dEOF	End of File
2			+	dEOFinSector	End of File in this sector (= last sector loaded)
3	+	+	+	dWritePending	Something was written to sector, it must be saved to Card, before loading next sector
4		+		dFATSector	This is an FAT Sector, at writing to Card, Number of FAT copies must be checked and copy updated if necessary
5			+	dFileEmpty	File is empty, no sector (Cluster) is allocated in FAT to this file
6			+	dFATDIRWritePending	For this file FAT or directory was updated
7			+	dFATDirSaveAtEnd	Indicates, that FAT and Directory Information have only to be updated at FLUSH and CLOSE staements

Использование команд ввода-вывода в различных режимах

Команда	Input	Output	Append	Binary
Attr	+	+	+	+
Close	+	+	+	+
Put				+
Get				+
LOF	+	+	+	+
LOC	+	+	+	+
EOF	+			+
SEEK (Get Position)	+	+	+	+
SEEK (Set Position)				+
Line Input	+			+
Print		+	+	+
Input	+			+
Write		+	+	+

Поддерживаемые выражения и функции: INITFILESYSTEM , OPEN , CLOSE, FLUSH , PRINT, LINE INPUT, LOC, LOF , EOF , FREEFILE , FILEATTR , SEEK , BSAVE , BLOAD , KILL , DISKFREE , DISKSIZE , GET , PUT ,FILEDATE , FILETIME , FILEDATETIME , DIR , FILELEN , WRITE , INPUT