element14 Community
element14 Community
    Register Log In
  • Site
  • Search
  • Log In Register
  • Community Hub
    Community Hub
    • What's New on element14
    • Feedback and Support
    • Benefits of Membership
    • Personal Blogs
    • Members Area
    • Achievement Levels
  • Learn
    Learn
    • Ask an Expert
    • eBooks
    • element14 presents
    • Learning Center
    • Tech Spotlight
    • STEM Academy
    • Webinars, Training and Events
    • Learning Groups
  • Technologies
    Technologies
    • 3D Printing
    • FPGA
    • Industrial Automation
    • Internet of Things
    • Power & Energy
    • Sensors
    • Technology Groups
  • Challenges & Projects
    Challenges & Projects
    • Design Challenges
    • element14 presents Projects
    • Project14
    • Arduino Projects
    • Raspberry Pi Projects
    • Project Groups
  • Products
    Products
    • Arduino
    • Avnet & Tria Boards Community
    • Dev Tools
    • Manufacturers
    • Multicomp Pro
    • Product Groups
    • Raspberry Pi
    • RoadTests & Reviews
  • About Us
  • Store
    Store
    • Visit Your Store
    • Choose another store...
      • Europe
      •  Austria (German)
      •  Belgium (Dutch, French)
      •  Bulgaria (Bulgarian)
      •  Czech Republic (Czech)
      •  Denmark (Danish)
      •  Estonia (Estonian)
      •  Finland (Finnish)
      •  France (French)
      •  Germany (German)
      •  Hungary (Hungarian)
      •  Ireland
      •  Israel
      •  Italy (Italian)
      •  Latvia (Latvian)
      •  
      •  Lithuania (Lithuanian)
      •  Netherlands (Dutch)
      •  Norway (Norwegian)
      •  Poland (Polish)
      •  Portugal (Portuguese)
      •  Romania (Romanian)
      •  Russia (Russian)
      •  Slovakia (Slovak)
      •  Slovenia (Slovenian)
      •  Spain (Spanish)
      •  Sweden (Swedish)
      •  Switzerland(German, French)
      •  Turkey (Turkish)
      •  United Kingdom
      • Asia Pacific
      •  Australia
      •  China
      •  Hong Kong
      •  India
      • Japan
      •  Korea (Korean)
      •  Malaysia
      •  New Zealand
      •  Philippines
      •  Singapore
      •  Taiwan
      •  Thailand (Thai)
      • Vietnam
      • Americas
      •  Brazil (Portuguese)
      •  Canada
      •  Mexico (Spanish)
      •  United States
      Can't find the country/region you're looking for? Visit our export site or find a local distributor.
  • Translate
  • Profile
  • Settings
Avnet Boards Forums
  • Products
  • Dev Tools
  • Avnet & Tria Boards Community
  • Avnet Boards Forums
  • More
  • Cancel
Avnet Boards Forums
Avnet Boards General USB UART powered down with power switch
  • Forum
  • Documents
  • Members
  • Mentions
  • Sub-Groups
  • Tags
  • More
  • Cancel
  • New
Join Avnet Boards Forums to participate - click to join for free!
Actions
  • Share
  • More
  • Cancel
Forum Thread Details
  • State Not Answered
  • Replies 5 replies
  • Subscribers 353 subscribers
  • Views 501 views
  • Users 0 members are here
Related

USB UART powered down with power switch

Former Member
Former Member over 12 years ago

When the ZedBoard is powered down, it also powers down the Cypress UART connection and thus the host looses the virtual comport. The result is that you have to reconnect in your terminal application after you have powered the board up again with the possibility of losing a part of the output.

It seems this can be prevented by removing R146 and placing R147. Why is this not the default?

Kind regards,
Maarten

  • Sign in to reply
  • Cancel
  • bhfletcher
    0 bhfletcher over 12 years ago

    You could do that, but it's not necessary. The Cypress USB-UART driver has a persistent feature built-in. Once you have connected to your terminal, leave the terminal connected when you power down, when you power back up, the terminal will automatically reconnect.

    Bryan

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • Former Member
    0 Former Member over 12 years ago

    PuTTY will disconnect the moment the power is down and the port gone. It will not auto-reconnect.

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • bhfletcher
    0 bhfletcher over 11 years ago

    Just to close the loop on this, Cypress has released a new driver, and we have updated the USB-UART documentation for ZedBoard.

    Bryan

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • Former Member
    0 Former Member over 11 years ago

    Could you be so kind to add a link to where this new driver can be found?

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • Former Member
    0 Former Member over 11 years ago

    There is a link to the driver and installation instructions in the current revision of the Cypress USB to UART Setup Guide located on the ZedBoard documentation page:

     

    http://www.zedboard.org/documentation/1521

     

    -Gary

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
element14 Community

element14 is the first online community specifically for engineers. Connect with your peers and get expert answers to your questions.

  • Members
  • Learn
  • Technologies
  • Challenges & Projects
  • Products
  • Store
  • About Us
  • Feedback & Support
  • FAQs
  • Terms of Use
  • Privacy Policy
  • Legal and Copyright Notices
  • Sitemap
  • Cookies

An Avnet Company © 2026 Premier Farnell Limited. All Rights Reserved.

Premier Farnell Ltd, registered in England and Wales (no 00876412), registered office: Farnell House, Forge Lane, Leeds LS12 2NE.

ICP 备案号 10220084.

Follow element14

  • X
  • Facebook
  • linkedin
  • YouTube