The host uses this command to request the file information of a file stored on the device. File types include standard files (images and certificates), MagTek custom files (configuration, firmware), and in some cases even large data blob output (such as signature capture data). In many cases, the file information retrieved by this command have been sent by a host previously using Start Send File to Device (Secured) - Command 0xD811 or Start Send File to Device (Unsecured) - Command 0xD812. In other cases, such as retrieving file information of signature capture data, the data may originate with the device and the host uses this command to retrieve the information. Such information is not persistent, in the sense that the device does not retain it through power cycles.
The sequence of events is as follows:
1
Compose and send request
The host composes a command request in the format below, and sends it to the device.
2
The device sends a response in the format below. The response contains the file information.
3
If the file cannot be found, then a response of failure will be sent to the host.
Tag
Len
Value / Description
Typ
Req
Default
Tag
Len
Value / Description
Typ
Req
Default
If the request started successfully, the Request Status in the message wrapper is OK, Started / Running, All good / requested operation was successful.
D825 = Get File Info from Device - Command 0xD825
81
04
File ID from Table XXX
B
R
End of any wrappers, at minimum including Request Message
D825 = Get File Info from Device - Command 0xD825
81
04
File ID from Table XXX
B
R
A2
var
File transfer properties
T
R
/81
var
Length of File — This is the length of the file.
B
R
/82
01
Hash Checksum Type
0x04 = SHA-256
B
R
/83
20
Hash Checksum — Anticipated checksum calculated against the file, according to the standard specified in Hash Checksum Type.
B
R
A3
var
File Description — The values the host populated for convenience when it sent the file to help identify the file. Not all values are required.
T
R
/81
var
File Name — Maximum length 32 bytes. Reserved for future use.
B
O
Null
/82
var
File Label — Maximum length 16 bytes. Reserved for future use.
B
O
Null
/83
var
File Version — Maximum length 7 bytes. Reserved for future use.
B
O
Null
/84
var
File Date — Maximum length 20 bytes. Reserved for future use.
B
O
Null
End of any wrappers, at minimum including Response Message
Beginning of any wrappers, at minimum including Request Message
Beginning of any wrappers, at minimum including Response Message
Device responds
File not found
Table GFID-1 - Get File Info from Device - Request Data for Command 0xD825
Table GFID-2 - Response Data for Get File Info from Device - Command 0xD825
Table GFID-3 - Request Example
Table GFID-4 - Response Example
Note: For additional support, please contact MagTek Support.