GET
Action
Reads a byte from the hardware or software UART.
Reads data from a file opened in BINARY mode.
Syntax
GET #channel, var
GET #channel, var , [pos] [, length]
Remarks
GET in combination with the software/hardware UART is provided for compatibility with BASCOM-8051. It reads one byte
GET in combination with the AVR-DOS filesystem is very flexible and versatile. It works on files opened in BINARY mode and you can reads all data types.
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#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 postion 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 wil 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 255. The maximum length for a non-string array is 65535.
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
ASM
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current position |
goto new position first |
|
Byte: |
|
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_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 |
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Word/Integer: |
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_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 |
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Long/Single: |
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_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 |
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_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 |
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_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
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