{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T17:30:20Z","timestamp":1772213420650,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2020,3,30]],"date-time":"2020-03-30T00:00:00Z","timestamp":1585526400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We report the first time-synchronized protocol stack running on a crystal-free device. We use an early prototype of the Single-Chip micro Mote, SC\u03bcM, a single-chip 2 \u00d7 3 mm2 mote-on-a-chip, which features an ARM Cortex-M0 micro-controller and an IEEE802.15.4 radio. This prototype consists of an FPGA version of the micro-controller, connected to the SC\u03bcM chip which implements the radio front-end. We port OpenWSN, a reference implementation of a synchronized protocol stack, onto SC\u03bcM. The challenge is that SC\u03bcM has only on-chip oscillators, with no absolute time reference such as a crystal. We use two calibration steps \u2013 receiving packets via the on-chip optical receiver and RF transceiver \u2013 to initially calibrate the oscillators on SC\u03bcM so that it can send frames to an off-the-shelf IEEE802.15.4 radio. We then use a digital trimming compensation algorithm based on tick skipping to turn a 567 ppm apparent drift into a 10 ppm drift. This allows us to run a full-featured standards-compliant 6TiSCH network between one SC\u03bcM and one OpenMote. This is a step towards realizing the smart dust vision of ultra-small and cheap ubiquitous wireless devices.<\/jats:p>","DOI":"10.3390\/s20071912","type":"journal-article","created":{"date-parts":[[2020,4,1]],"date-time":"2020-04-01T03:44:13Z","timestamp":1585712653000},"page":"1912","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["6TiSCH on SC\u03bcM: Running a Synchronized Protocol Stack without Crystals"],"prefix":"10.3390","volume":"20","author":[{"given":"Tengfei","family":"Chang","sequence":"first","affiliation":[{"name":"EVA Team, Inria-Paris, 75012 Paris, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3695-9315","authenticated-orcid":false,"given":"Thomas","family":"Watteyne","sequence":"additional","affiliation":[{"name":"EVA Team, Inria-Paris, 75012 Paris, France"}]},{"given":"Brad","family":"Wheeler","sequence":"additional","affiliation":[{"name":"EECS Department, UC Berkeley, Berkeley, CA 94720-1770, USA"}]},{"given":"Filip","family":"Maksimovic","sequence":"additional","affiliation":[{"name":"EECS Department, UC Berkeley, Berkeley, CA 94720-1770, USA"}]},{"given":"Osama","family":"Khan","sequence":"additional","affiliation":[{"name":"EECS Department, UC Berkeley, Berkeley, CA 94720-1770, USA"}]},{"given":"Sahar","family":"Mesri","sequence":"additional","affiliation":[{"name":"EECS Department, UC Berkeley, Berkeley, CA 94720-1770, USA"}]},{"given":"Lydia","family":"Lee","sequence":"additional","affiliation":[{"name":"EECS Department, UC Berkeley, Berkeley, CA 94720-1770, USA"}]},{"given":"Ioana","family":"Suciu","sequence":"additional","affiliation":[{"name":"IN3, University Oberta de Catalunya, 08035 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9686-6690","authenticated-orcid":false,"given":"David","family":"Burnett","sequence":"additional","affiliation":[{"name":"EECS Department, UC Berkeley, Berkeley, CA 94720-1770, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3020-427X","authenticated-orcid":false,"given":"Xavier","family":"Vilajosana","sequence":"additional","affiliation":[{"name":"IN3, University Oberta de Catalunya, 08035 Barcelona, Spain"}]},{"given":"Kris","family":"Pister","sequence":"additional","affiliation":[{"name":"EECS Department, UC Berkeley, Berkeley, CA 94720-1770, USA"}]}],"member":"1968","published-online":{"date-parts":[[2020,3,30]]},"reference":[{"key":"ref_1","unstructured":"(2020, March 30). 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