Camera Link registers
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Goldeye Camera Link Register Controls Reference V1.0.0
Further Issues to consider when programming GenCP
•
On Windows systems, the serial port of a frame grabber is accessed through a
DLL provided by the grabber manufacturer. The DLL's name usually is
"clserXYZ.dll" where XYZ denotes the grabber manufacturer. The DLL's API
however is standardized and is described in the AIA Camera Link specification.
GenCP command packet data has to be written using the "clSerialWrite"
function while acknowledge packet data can be read using the "clSerialRead"
function.
•
An Allied Vision GenCP Camera Link camera always starts up with a baud rate
of 9600 bits per second. It is possible to change this value if required, but this
requires following a special command sequence described in the GenCP stan-
dard. It is not repeated here.
•
Commands must not be transferred in bursts. Before a new command is sent,
the host must wait for the reception of the previous acknowledge packet.
•
If an acknowledge to a command packet is not received within a command tim-
eout period of time, the command may be resent by the host with the Com-
mandResend flag set up to 3 times. The Round Trip Time (RTT) for a
command and acknowledge can be calculated by RTT = Command Transfer
Time + Processing Time + Acknowledge Transfer Time. The Maximum Device
Response Time (MDRT) can be queried via the MDRT bootstrap register. The
MDRT for reading the MDRT register should not exceed 50ms.
•
Since Allied Vision Camera Link cameras do not yet support pending
acknowledges, the RTT can be considered as the command timeout period.
Otherwise the host must consider the transfer time, Maximum Device
Response Time and some margin for technology-dependent delays in order to
calculate the command timeout period.
•
If a command packet is corrupted or lost while it is sent to the camera, the
camera will discard it and send no reply. After the command timeout expired,
the host may resend the packet.
•
An acknowledge packet is considered as lost, if the command timeout has
expired. The host may resend the packet. If the host receives a corrupted
acknowledge packet, it will discard it and may resend the packet without
waiting for the command timeout to expire. Since the CommandResend flag is
then set, the camera will detect, that this packet was already processed. It will
then resend the acknowledge packet without changing its state.
•
Allied Vision Camera Link cameras do not yet support pending acknowledges
and event packets.
