{
  "@context":[
    "https://www.w3.org/ns/activitystreams",
    {"Hashtag":"as:Hashtag"}
  ],
  "published":"2023-07-03T20:31:37.325Z",
  "attributedTo":"https://krall.sh/actors/evan",
  "to":["https://www.w3.org/ns/activitystreams#Public"],
  "cc":["https://krall.sh/actors/evan/followers"],
  "content":"<p>This weekend I wrote two decoders for TI's HDQ protocol -- one in the Linux kernel for my pipad project, and one as an analyzer plug-in for Saleae Logic so I could debug the first one.</p><p>The kernel implementation is kinda janky, but the Logic plugin is pretty decent. It's actually a generic PWM serial decoder -- should handle any simple serial protocol where the value of the bit is encoded by the length of a pulse.</p><figure><img src=\"https://krall.sh/uploads/6f2a4fdb/c675/499e/1.png\" width=\"1191\" height=\"455\"><figcaption>Screenshot of the Saleae Logic 2 program with my analyzer plugin enabled. Squiggly lines represent the logic level (high or low voltage), and text bubbles above each group of 8 bits show the decoded value.</figcaption></figure><p><br><a href=\"https://github.com/EvanKrall/raspberrypi-linux/commit/354e1a71079559d1b2cded459980322dfb2adcc5\">https://github.com/EvanKrall/raspberrypi-linux/commit/354e1a71079559d1b2cded459980322dfb2adcc5<br></a></p><p><a href=\"https://github.com/EvanKrall/pwm_serial_analyzer\">https://github.com/EvanKrall/pwm_serial_analyzer</a></p>",
  "mediaType":"text/html",
  "attachment":[{"url":"https://krall.sh/uploads/6f2a4fdb/c675/499e/1.png","mediaType":"image/png"}],
  "type":"Note",
  "id":"https://krall.sh/objects/5I_ohxlezzY"
}