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Showing results for tags 'usb2.0'.
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Hi, I'm working on a project based on a Xilinx Ultrascale+. The final board will contain, for JTAG interface, a SMT2-NC device with a USB type-C receptacle. This board should work as "device", and so as Upstream Facing Port (UFP). At the moment, I know how to treat the CC lines (via 5.1 kOhm pull-down resistors) but I still don't understand how to connect (or how to use) the VBUS lines, because the SMT2 is powered from the 3.3V and VREF pins and not VBUS. Can I leave the VBUS lines unconnected or I should follow some specific procedure to connect them? Thanks
Interested to know of techniques for transferring (streaming) data from a FPGA Eval Board to a PC. Looks like 15 years ago there was DPCUTIL as part of the Adept suite. Is this still currently used or has it been superseded? I have a Gensys 2 board which purports to have a PC - FPGA Data Transfer (DPTI/DSPI) via a FT2232 USB Controller however according to the schematics this doesn't seem to be populated on my version of the board. Is there an easy way of finding what versions of the FPGA Eval boards offer this? Do any of the current generation of FPGA Eval Boards offer the newer FT600/FT601 series of controller which has options for a high speed USB3.0 pipe as well as USB2.0 breakout to SPI JTAG etc for control?
I've measured the Analog Discovery 2 drawing a current of 510 mA over USB. The USB 2.0 specification  dictates that devices shall not draw an absolute maximum current greater than 100 mA before configuration and shall not draw an absolute maximum current greater than 500 mA once configured. It appears to me that the AD2 is not compliant with the USB 2.0 specification. This could explain the Waveforms 2015 errors messages that I reported in another thread on this forum . Measurements were taken on a "warm" AD2 that had already been operating; I anticipate peak current on an AD2 that has been disconnected for some period will be higher (capacitances discharged). Measurements were performed with the AD2 running solely from USB power. Measurements were taken while connecting the AD2 to a PC on which the Waveforms 2015 software was already running. Measurements were not taking during AD2 acquisition or waveform generation operations. Didn't get a photo of the 510.1 mA measurement, but a photo of a 507.7 mA measurement is attached. The measurements were made with a Fluke 87V in mA DC mode with the range manually fixed to "600". The large currents were detected using peak-min-max mode (250 microsecond response time). The large currents were not detected using regular min-max mode (100 millisecond response time). The USB 2.0 spec makes the peripheral responsible for limiting its in-rush current and implementing soft-start as needed. -- Chris  http://www.usb.org/developers/docs/usb20_docs/usb_20_120516.zip --> usb_20.pdf, sections 7.2.1 and 22.214.171.124  https://forum.digilentinc.com/topic/3226-waveforms-2015-jtscinitscanchain-failed-error-dptiio-failed-error-ubuntu-16041-x86-64-analog-discovery-2-analog-discovery-2/#comment-11671