GET

GET

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Action

Reads a byte from the hardware or software UART.

Reads data from a file opened in BINARY mode.

 

 

Syntax UART

GET #channel, var

 

Syntax DOS

GET #channel, var

GET #channel, var , [pos] [, length]

 

 

Remarks

GET in combination with the software/hardware UART reads one byte from the UART.

GET in combination with the AVR-DOS file system is very flexible and versatile. It works on files opened in BINARY mode and you can reads all data types.

 

#channel

A channel number, which identifies an opened file. This can be a hard coded constant or a variable.

Var

The variable or variable array that will be assigned with the data from the file

Pos

This is an optional parameter that may be used to specify the position where the reading must start from. This must be a long variable.

Length

This is an optional parameter that may be used to specify how many bytes must be read from the file.

 

By default you only need to provide the variable name. When the variable is a byte, 1 byte will be read. When the variable is a word or integer, 2 bytes will be read. When the variable is a long or single, 4 bytes will be read. When the variable is a string, the number of bytes that will be read is equal to the dimensioned size of the string. DIM S as string * 10 , would read 10 bytes.

 

Note that when you specify the length for a string, the maximum length is 254. The maximum length for a non-string array is 65535.

 

In BASCOM-8051, GET was implemented to read only from the UART. While BASCOM-AVR supports GET for the UART, its primary purpose is to read from files with AVR-DOS. For the UART, GET is limited to read 1 byte, just like WAITKEY.

 

 

Partial Example :

GET #1 , var ,,2          ' read 2 bytes, start at current position

GET #1, var , PS                 ' start at position stored in long PS

GET #1, var , PS, 2         ' start at position stored in long PS and read 2 bytes

 

 

See also

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

 

 

 

ASM

current position

goto new position first

Byte:

 

_FileGetRange_1

 

Input:

 

r24: File number

 

X: Pointer to variable

 

T-Flag cleared

_FileGetRange_1

 

Input:

 

r24: File number

 

X: Pointer to variable

 

r16-19 (A): New position (1-based)

 

T-Flag Set

Word/Integer:

 

_FileGetRange_2

 

Input:

 

r24: File number

 

X: Pointer to variable

 

T-Flag cleared

_FileGetRange_2

 

Input:

 

r24: File number

 

X: Pointer to variable

 

r16-19 (A): New position (1-based)

 

T-Flag Set

Long/Single:

 

_FileGetRange_4

 

Input:

 

r24: File number

 

X: Pointer to variable

 

T-Flag cleared

_FileGetRange_4

 

Input:

 

r24: File number

 

X: Pointer to variable

 

r16-19 (A): New position (1-based)

 

T-Flag Set

String (<= 255 Bytes) with fixed length

 

_FileGetRange_Bytes

 

Input:

 

r24: File number

 

r20: Count of Bytes

 

X: Pointer to variable

 

T-Flag cleared

_FileGetRange_Bytes

 

Input:

 

r24: File number

 

r20: Count of bytes

 

X: Pointer to variable

 

r16-19 (A): New position (1-based)

 

T-Flag Set

Array (> 255 Bytes) with fixed length

 

_FileGetRange

 

Input:

 

r24: File number

 

r20/21: Count of Bytes

 

X: Pointer to variable

 

T-Flag cleared

_FileGetRange

 

Input:

 

r24: File number

 

r20/21: Count of bytes

 

X: Pointer to variable

 

r16-19 (A): New position (1-based)

 

T-Flag Set

 

 

Output from all kind of usage:

r25: Error Code

C-Flag on Error

X: requested info

 

 

Partial Example

'for the binary file demo we need some variables of different types

Dim B As Byte , W As Word , L As Long , Sn As Single , Ltemp As Long

Dim Stxt As String * 10

B = 1 : W = 50000 : L = 12345678 : Sn = 123.45 : Stxt = "test"

 

'open the file in BINARY mode

Open "test.biN"for Binary As #2

Put#2 , B ' write a byte

Put#2 , W ' write a word

Put#2 , L ' write a long

Ltemp = Loc(#2) + 1                                         ' get the position of the next byte

Print Ltemp ; " LOC"                                       ' store the location of the file pointer

Print Seek(#2) ; " = LOC+1"

 

Print Lof(#2) ; " length of file"

Print Fileattr(#2) ; " file mode"                         ' should be 32 for binary

Put #2 , Sn                                                 ' write a single

Put #2 , Stxt                                               ' write a string

 

Flush #2                                                   ' flush to disk

Close #2

 

'now open the file again and write only the single

Open "test.bin" For Binary As #2

L = 1 'specify the file position

B = Seek(#2 , L)                                           ' reset is the same as using SEEK #2,L

Get#2 , B ' get the byte

Get#2 , W ' get the word

Get#2 , L ' get the long

Get#2 , Sn ' get the single

Get#2 , Stxt ' get the string

Close #2