Alkeria NECTA Series - Bandwidth Limit for Bulk Endpoint

8. Capturing Images 100
USB Packet size Burst size Number of bursts Bytes per micro-frame Bandwidth
1 KiB × 3 × 1 3 KiB 24 000 KiB/s
1 KiB × 6 × 1 6 KiB 48 000 KiB/s
1 KiB × 8 × 1 8 KiB 64 000 KiB/s
1 KiB × 10 × 1 10 KiB 80 000 KiB/s
1 KiB × 11 × 1 11 KiB 88 000 KiB/s
1 KiB × 12 × 1 12 KiB 96 000 KiB/s
1 KiB × 13 × 1 13 KiB 104 000 KiB/s
1 KiB × 14 × 1 14 KiB 112 000 KiB/s
1 KiB × 15 × 1 15 KiB 120 000 KiB/s
1 KiB × 8 × 2 16 KiB 128 000 KiB/s
1 KiB × 9 × 2 18 KiB 144 000 KiB/s
1 KiB × 10 × 2 20 KiB 160 000 KiB/s
1 KiB × 11 × 2 22 KiB 176 000 KiB/s
1 KiB × 12 × 2 24 KiB 192 000 KiB/s
1 KiB × 14 × 2 28 KiB 224 000 KiB/s
1 KiB × 16 × 2 32 KiB 256 000 KiB/s
1 KiB × 12 × 3 36 KiB 288 000 KiB/s
1 KiB × 13 × 3 39 KiB 312 000 KiB/s
1 KiB × 14 × 3 42 KiB 336 000 KiB/s
1 KiB × 15 × 3 45 KiB 360 000 KiB/s
1 KiB × 16 × 3 48 KiB 384 000 KiB/s
Table 8.2: Available isochronous alternate settings
Example Code 8.12 | Sets a bandwidth limits of 32 KiB per microframe on NECTA
device.SetBandwidthLimits(new uint[] {32});
Note
When calling the SetBandwidthLimits method, a valid alt-interface band-
width –expressed as bytes per micro-frame– must be selected. To get a list
of all available bandwidth-limit values the GetAllowedBandwidthLimits
method can be invoked.
8.9.3 Bandwidth limit for bulk endpoint
In bulk endpoint mode the burst size is xed at x16, resulting in a 16 KiB of data per bulk request. The
bandwidth limit control can be seen as the average data transferred every 125 µs but has no effect on
the burst size itself.