Allied Vision Goldeye, Manual

Page: 19 / 133

Camera Link registers
19 Goldeye Camera Link Register Controls Reference V1.0.0
GenCP WriteMem Command Packet Layout
In order to write to a camera register, the host has to issue a
WriteMem Command
.
The command consists of a single packet that is described in the following tables.
Offset
[Bytes]
Size
[Bytes] Name Description
0 2 Preamble Preamble that contains the bytes
0x01
and
0x00
.
2 2 CCD
Checksum 16 bit checksum that is built over the channel_id and the CCD of
the packet. Note that this is not a classic CRC calculation as
suggested by the standard! Please refer to
GenCP Checksum
Calculation Function on page 7-21 for more information.
4 2 SCD
Checksum 16 bit checksum that is built over channel_id, CCD and SCD of
the packet. Note that this is
not a classic CRC calculation as
suggested by the standard! Please refer to GenCP Checksum
Calculation Function on page 7-21 for more information.
6 2 channel_id This value is
0
for the communication channel.
Table 9: WriteMem Command packet layout - Subrange: Serial prefix
Offset
[Bytes]
Size
[Bytes] Name Description
8 2 flags Bit 0..13: reserved (=
0
)
Bit 14:
RequestAck
(must be set if the sender commands an
acknowledge packet from the camera. This will usually be
1
.)
Bit 15:
CommandResend
(This bit should be set, if the host did not
receive a valid reply to a previous command. In this case the
packet can be resent with this bit set.)
10 2 command_id This value is
0x0802
for
WriteMem
commands.
12 2 length Defines the length of the SCD part of the packet. For
WriteMem
commands, this value is 8 + payload length. The GenCP standard
recommends to not generate packets with more than 1000
bytes of payload data.
14 2 request_id This is a packet identifier that should be incremented by the host
each time it issues a new command. If resending a packet, the
request_id should be the same as in the original packet.
Table 10: WriteMem Command packet layout - Subrange: CCD
Offset
[Bytes]
Size
[Bytes] Name Description
16 8 register
address This is a 64 bit value defining the address to write to.
24 8 payload This is the payload data that is to be written to the camera.
Table 11: WriteMem Command packet layout - Subrange: SCD