Magtek eDynamo - Command 0 X4 A - Get Extended Response (Extended Commands Only)

8 - Commands
eDynamo| Secure Card Reader Authenticator | Programmer’s Manual (COMMANDS)
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8.3.16 Command 0x4A - Get Extended Response (Extended Commands Only)
The host uses this command to retrieve additional response data longer than the current connection type’s
maximum packet size. After calling a command, if the device returns generic result code 0x0A Extended
response first packet (see Table 8-3 - Generic Result Codes on page 67), the host software should
begin buffering the complete Extended Response starting with the initial response, then call this
command repeatedly until it has retrieved the complete Extended Response.
The response data from the device follows the same Extended Data Offset rule as Command 0x49 - Send
Extended Command Packet from the host: The first packet the device sends to the host specifies
Extended Data Offset = 0, and subsequent packets, if any, specify Extended Data Offset = 52 (or other
packet length depending on connection type), then 104, 156, and so on, until the device has sent all the
response data. The host should continue sending this command to the device and buffering the returned
Extended Data until the Extended Data Offset plus the length of the Extended Data equals the Complete
Extended Data Length.
Request Data: None
Table 8-34 - Response Data for Command 0x4A - Get Extended Response (Extended Commands Only)
Offset
Field Name
Description
0..1
Extended Data
Offset
This field is in big endian format. It indicates the byte offset position of this
packet’s Extended Data field, relative to the complete extended data field
being sent as multiple packets. The first byte is offset zero.
2..3
Extended
Result Code
This field is in big endian format. For one byte result codes, the high byte is
set to zero.
4..5
Complete
Extended Data
Length
This field is in big endian format and gives the total length of the extended
data field the device is returning to the host in multiple packets. If the
complete extended data fits in a single packet, this field is equal to the Data
Length field minus 6.
6..n
Extended Data
This field contains either part or all of the extended data the device is sending
to the host. The size of this Extended Data field can be determined by
subtracting the Extended Data field’s offset within the response (6) from the
response’s total data length (N). In most cases the response’s complete data
payload can have a maximum value of 58 (for example see section 2.1.2 How
to Send Commands On the USB Connection), so this field can have a
maximum length of 58 - 6 = 52 bytes.
Result Codes: Same as defined in Command 0x49 - Send Extended Command Packet.
Example Request (Hex)
Cmd Num
Data Len
Data
4A
00
Example Response (Hex)
Result Code
Data Len
Data
0A
09
00 34 00 00 00 37 35 36 37
(Last 3 bytes of extended data out of 55 bytes)