Recent Changes

Thursday, May 31

  1. user_add lbassham lbassham joined WISP5
    3:10 pm
  2. 3:10 pm

Tuesday, January 30

  1. user_add linchkong linchkong joined WISP5
    7:48 am
  2. user_add Chris1229 Chris1229 joined WISP5
    7:48 am

Monday, January 22

  1. page WISP Home edited ... Welcome to the WISP 5 Wiki! This project is supported in part by NSF Grant CNS-1305072, entit…
    ...
    Welcome to the WISP 5 Wiki!
    This project is supported in part by NSF Grant CNS-1305072, entitled "CI-ADDO-EN: Infrastructure for the RF-Powered Computing Community." Additional support from NSF Grant EEC-1028725, Intel Corporation, Disney Corporation, and the Google Faculty Research Awards program.
    Thanks to JaeMin Shin and everyone in the Computer Network Lab at South Korea's Sungkyunkwan University for their contribution of a version of the WISP code that can operate with the Asian version of Impinj Speedway R420 readers, the R420-GX2!! Find the new WISP5 firmware repository branch here.
    {wisp5-frontside-sm.png}
    The Wireless Identification and Sensing Platform (WISP) is an open source and fully hackable battery-free platform for experimentation with low power sensing, computation, and communication. This wiki is a place for users and developers of the WISP to compile resources related to the WISP, to share knowledge, and to collaborate on large scale projects.
    (view changes)
    12:24 pm
  2. page WISP Home edited ... The WISP5 is the latest iteration of the WISP. For resources related to earlier WISP versions,…
    ...
    The WISP5 is the latest iteration of the WISP. For resources related to earlier WISP versions, see wisp.wikispaces.com.
    Looking for an NFC based WISP? The NFC-WISP interfaces with smartphone readers and more! See the new nfc-wisp wiki to learn more!
    ...
    in version 5.0/5.15.0/5.1:
    New! Compatibility with Impinj R420 readers sold in Asia (R420-GX2). See the 436kHz branch of the wisp5 firmware repository to get your WISPs talking to readers not sold in the USA.
    Energy-optimized firmware stack with support for FM0 modulation and simpler application interface.
    (view changes)
    12:20 pm
  3. page WISP Home edited ... Looking for an NFC based WISP? The NFC-WISP interfaces with smartphone readers and more! See t…
    ...
    Looking for an NFC based WISP? The NFC-WISP interfaces with smartphone readers and more! See the new nfc-wisp wiki to learn more!
    New features in version 5.0/5.1
    New! Compatibility with Impinj R420 readers sold in Asia (R420-GX2). See the 436kHz branch of the wisp5 firmware repository to get your WISPs talking to readers not sold in the USA.
    Energy-optimized firmware stack with support for FM0 modulation and simpler application interface.
    Read and Write command support out of the box.
    (view changes)
    12:20 pm

Tuesday, January 16

  1. msg WISP 5.0 Modification to operate with Impinj R420 Asian version( message posted WISP 5.0 Modification to operate with Impinj R420 Asian version( Hello, We are pleased to share the source code of WISP 5.0 operating at "436kHz/FM0".…
    WISP 5.0 Modification to operate with Impinj R420 Asian version(
    Hello,

    We are pleased to share the source code of WISP 5.0 operating at "436kHz/FM0".

    Currently, the WISP 5.0 "640kHz" branch only works on FCC-compliant Impinj Speedway R420 readers.
    However, FCC-compliant R420 readers are not available in Asia.

    We found that the asian version R420(R420-GX2) does not support 640kHz/FM0 (UHFRFModeTable configuration),
    but provides 436kHz/FM0 ( with 16.67us Tari Value ).

    So we have modified the WISP 5.0 code to work at 436kHz (and also reduced TxClock from 12MHz to 8MHz).
    The modifed WISP 5.0 "436kHz/FM0" supports Query, Query Repeat, Ack, and Query Adjust commands for "basic simple Ack demonstration".


    Here is the github address.
    https://github.com/whitecloudy/wisp5
    Please use 436kHz branch


    Please send your question, comment or bug report to the following email address.

    JaeMin Shin alex9395@naver.com
    Yusung Kim yskim525@skku.edu / yskim525@gmail.com

    Computer Network Lab.
    Sungkyunkwan University

    Or Github Issue board is also available.

    https://github.com/whitecloudy/wisp5/issues
    1:24 am

Monday, December 4

  1. msg Query Reply command process message posted Query Reply command process I've found the answer my above question in the EPC C1G1 material. Thank you for reading. 6.3.2.1…
    Query Reply command process
    I've found the answer my above question in the EPC C1G1 material. Thank you for reading.

    6.3.2.10 Inventorying Tag populations
    The inventory command set includes Query, QueryAdjust, QueryRep, ACK, and NAK. Query initiates an inventory round and decides which Tags participate in the round (“inventory round” is defined in 4.1).
    Query contains a slot-count parameter Q. Upon receiving a Query participating Tags pick a random value in the range (0, 2Q–1), inclusive, and load this value into their slot counter. Tags that pick a zero transition to the reply state and reply immediately. Tags that pick a nonzero value transition to the arbitrate state and await a QueryAdjust or QueryRep command.
    12:30 am

Sunday, December 3

  1. msg WISP5 with making use of BQ25570 message posted WISP5 with making use of BQ25570 Dear all, I'm fabricating my own WISP. I'd like to use BQ25570 as indicated in WISP Camera paper…
    WISP5 with making use of BQ25570
    Dear all,

    I'm fabricating my own WISP. I'd like to use BQ25570 as indicated in WISP Camera paper. I've already bought BQ25570 EVM for testing. My application circuit needs at least 2V and 2.6V for MCU and sensor to operate, respectively.

    Here is what I'm doing. The Vout (regulating output) was pre-set to 1.8V in the EVM, so it does not satisfy my circuit requirement. So I connect my ending circuit with VBAT with the hope to successfully boost the input voltage up to 2.6V. The BQ25570 was fed by 2-stage Dickson charge bump. However it's never reached that voltage. Instead the maximum voltage I got from VBAT or VSTOR was under 2V with my configuration, even not enough to operate the MCU. Without BQ25570, 2-stage Dickson charge bump can give 2.6V with the RF input power of 3dBm at 20cm.

    I do not know what's wrong with my configuration. Please anyone recommend the correct/working configuration? Thank you for any advice.
    5:34 pm

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