Basler slA1000-30fm, Руководство пользователя

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Using Multiple Cameras on a Single Bus and Managing Bandwidth
134 Basler scout light
that we could have made the packet sizes smaller and thus the total byte load per cycle would be
less than the maximum allowed. It is OK to make the total byte load smaller than the maximum, but
not larger.
Fig. 35: Packet Transmission During Bus Cycles
A parameter called the Packet Size is used to set the size of the packet that the camera will transmit
on each cycle of the bus. For an IEEE 1394b camera attached to an IEEE 1394b bus, the minimum
value for this setting is 1 byte and the maximum is 8192 bytes. If you set the packet size to 8192,
the camera will use 100% of the available bus bandwidth when it is transmitting images. If you set
the bytes per packet to a lower value, the camera will use less of the bandwidth. For example, if you
set the value to 5120 (62.5% of 8192), then the camera will send 5120 byte packets when it is
transmitting image data and will use 62.5% of the available bus bandwidth.
You can set the value of the Packet Size parameter from within your application software by using
the pylon API. The following code snippet illustrates using the API to set the parameter value:
// Set packet size
Camera.PacketSize.SetValue( 4096 );
For detailed information about using the pylon API, refer to the Basler pylon Programmer’s Guide
and API Reference.
You can also use the Basler pylon Viewer application to easily set the parameter.
For more information about the pylon Viewer, see Section 3.1 on page 17 .
125 µs
8192 Byte Packet Camera A
2048 Byte
Packet
Camera A
2048 Byte
Packet
Camera B
4096 Byte
Packet
Camera C
125 µs
125 µs
125 µs
2048 Byte
Packet
Camera A
2048 Byte
Packet
Camera B
4096 Byte
Packet
Camera C
8192 Byte Packet Camera A
Situation 1:
Situation 2: