ALLIED Vision Technologies Guppy PRO F-503 - Manual (Page 186)

Video formats, modes and bandwidth
Guppy PRO Technical Manual V4.0.0
184
Frame rates
An IEEE 1394 camera requires bandwidth to transport images.
The IEEE 1394b bus has very large bandwidth of at least 62.5 MByte/s for
transferring (isochronously) image data. Per cycle up to 8192 bytes (or
around 2000 quadlets = 4 bytes@ 800 Mbit/s) can thus be transmitted.
Depending on the video format settings and the configured frame rate, the
camera requires a certain percentage of maximum available bandwidth.
Clearly the bigger the image and the higher the frame rate, the more data is
to be transmitted.
The following tables indicate the volume of data in various formats and
modes to be sent within one cycle (125 µs) at 800 Mbit/s of bandwidth.
The tables are divided into three formats:
They enable you to calculate the required bandwidth and to ascertain the
number of cameras that can be operated independently on a bus and in which
mode.
Note

Configuration
To configure this feature in an advanced register see Chapter
Autofunction AOI on page 256.
Note

All bandwidth data is calculated with:
1 MByte = 1024 kByte
Format Resolution Max. video format
Format_0 up to VGA 640 x 480
Format_1 up to XGA 1024 x 768
Format_2 up to UXGA 1600 x 1200
Table 86: Overview fixed formats