ShimmerResearch · marknolan · Sep 17, 2026 · Sep 17, 2026
@@ -488,14 +488,16 @@ Three things that take the sensor's link exclusively for a while. (The red LED
 used to be here too; it is on **General** now, because nothing about it is a
 test.)
 
-**Link speed** free-runs the firmware's data-rate test for five seconds and
+**Throughput** free-runs the firmware's data-rate test for five seconds and
 counts what arrives, which is the only honest way to know a link's throughput:
 BLE negotiates its connection interval with the host's own Bluetooth stack, so
-two hosts and the same sensor can differ severalfold. It is Bluetooth-only —
-the dock command set has no data-rate test — and refused while the sensor is
-sensing or a transfer is running, because it saturates the link on purpose. The
-figure lands in the SD card tab's stats and drives its download estimates, so
-measuring once after connecting makes those estimates worth reading.
+two hosts and the same sensor can differ severalfold. It is named for what it
+measures rather than for a link, but on this sensor only the Bluetooth ones can
+run it — the dock command set has no data-rate test at all. It is refused
+while the sensor is sensing or a transfer is running, because it saturates the
+link on purpose. The figure lands in the
+SD card tab's stats and drives its download estimates, so measuring once after
+connecting makes those estimates worth reading.
 
 It used to sit beside the connect buttons. It is here now because it is a test
 that holds the link, which is what everything else on this tab does, and it

@@ -964,7 +964,7 @@ <h1>Shimmer Capture</h1>
              gating machinery with them. The connect row is where the eye
              should land on the primary action. -->
         <div class="card">
-          <div class="card-title">Link speed</div>
+          <div class="card-title">Throughput test</div>
           <div class="field-hint" id="linkTestNote"></div>
           <div class="row">
             <button
@@ -973,7 +973,7 @@ <h1>Shimmer Capture</h1>
               data-requires="idle"
               data-cap="linkTest"
             >
-              Measure link speed (5 s)
+              Measure throughput (5 s)
             </button>
             <span class="pill" id="linkSpeedPill">not measured</span>
           </div>
@@ -1783,7 +1783,7 @@ <h1>Shimmer Capture</h1>
           $("applyNote").textContent = plan.blocked;
         } else if (linkTesting) {
           $("applyNote").textContent =
-            "Waiting for the link-speed test to finish — it saturates the link on purpose, which is the whole point of it.";
+            "Waiting for the throughput test to finish — it saturates the link on purpose, which is the whole point of it.";
         } else if (sdBusy) {
           /* Not the firmware refusing this time — the page is. One link, one
                    conversation: a configuration write in the middle of a file
@@ -3654,7 +3654,7 @@ <h1>Shimmer Capture</h1>
                  three (see its setEnabled call), so leaving them unsaid greyed the
                  card out with no reason on screen. */
         if (linkTesting) {
-          return "The link-speed test is running. It saturates the link on purpose — wait the few seconds for it to finish.";
+          return "The throughput test is running. It saturates the link on purpose — wait the few seconds for it to finish.";
         }
         if (brandBusy) {
           return "A device-naming write is using the link. A download and a name write cannot share it — wait for it to finish.";
@@ -3856,7 +3856,7 @@ <h1>Shimmer Capture</h1>
           return "The sensor is sensing, and the firmware refuses every configuration command while it is. Stop the stream before reading or writing calibration.";
         }
         if (linkTesting) {
-          return "The link-speed test is running. It saturates the link on purpose — wait the few seconds for it to finish.";
+          return "The throughput test is running. It saturates the link on purpose — wait the few seconds for it to finish.";
         }
         if (sdBusy) {
           return "An SD card transfer is using the link. A calibration write and a download cannot share it — wait for the transfer to finish.";
@@ -3902,7 +3902,7 @@ <h1>Shimmer Capture</h1>
           return "The sensor is sensing, and the firmware refuses a self-test while it is — the test takes the whole sensor over for up to a minute. Stop the stream first.";
         }
         if (linkTesting) {
-          return "The link-speed test is running. It saturates the link on purpose — wait the few seconds for it to finish.";
+          return "The throughput test is running. It saturates the link on purpose — wait the few seconds for it to finish.";
         }
         if (sdBusy) {
           return "An SD card transfer is using the link. A report printed into the middle of a block stream would interleave with it — wait for the transfer to finish.";
@@ -3974,7 +3974,7 @@ <h1>Shimmer Capture</h1>
         if (!client) return "disconnected";
         if (testBusy) return "the self-test is running";
         if (streaming || sdLogging) return "the sensor is sensing";
-        if (linkTesting) return "the link-speed test is running";
+        if (linkTesting) return "the throughput test is running";
         if (sdBusy) return "an SD card transfer is using the link";
         if (brandBusy) return "a device-naming write is using the link";
         if (calibBusy) return "a calibration write is using the link";
@@ -4094,7 +4094,7 @@ <h1>Shimmer Capture</h1>
           return "The sensor is sensing. New names only take effect when it restarts, and the firmware skips a restart while it is sensing so a recording can never be truncated — stop the stream before changing the names.";
         }
         if (linkTesting) {
-          return "The link-speed test is running. It saturates the link on purpose — wait the few seconds for it to finish.";
+          return "The throughput test is running. It saturates the link on purpose — wait the few seconds for it to finish.";
         }
         if (sdBusy) {
           return "An SD card transfer is using the link. A name write and a download cannot share it — wait for the transfer to finish.";

@@ -209,7 +209,7 @@ check(
   linkOrder.ids.join(" → "),
 );
 
-// --- 4. the link-speed button's new home, before anything is connected ----
+// --- 4. the throughput button's new home, before anything is connected ----
 const linkIdle = await evaluate(`
   const sdk = await import('/vendor/shimmer-web-sdk.esm.js');
   const btn = document.getElementById('btnLinkTest');
@@ -234,7 +234,7 @@ check(
   /* Twice moved: out of the SD panel, then out of the connect column. It is a
      test that takes the link exclusively, which is what the Test tab is for,
      and its result is still read by the SD panel's own estimates. */
-  "the link-speed button lives in the Test tab, not the SD panel or the connect column",
+  "the throughput button lives in the Test tab, not the SD panel or the connect column",
   linkIdle.inTestTab &&
     linkIdle.notInLinkCard &&
     linkIdle.notInSdPanel &&
@@ -905,7 +905,7 @@ check(
   `${sdDelete.before.length} → ${sdDelete.after.length} files, ${sdDelete.deleteCmds} SD_DELETE commands`,
 );
 
-// ---- the link-speed test
+// ---- the throughput test
 const sdLink = await evaluate(`
   await window.sdBrowser.measureLinkSpeed(1200);
   // The event log flushes on an animation frame, so the last lines are not
@@ -915,11 +915,11 @@ const sdLink = await evaluate(`
     on: window.mockTransport.writes.some(w => w.bytes[0] === 0xA4 && w.bytes[1] === 1),
     off: window.mockTransport.writes.some(w => w.bytes[0] === 0xA4 && w.bytes[1] === 0),
     guide: [...document.querySelectorAll('#log .log-line')].map(l => l.textContent)
-      .filter(l => /raw link speed: |as a guide|currently on this card/.test(l)) };
+      .filter(l => /raw throughput: |as a guide|currently on this card/.test(l)) };
 `);
 const linkKBps = Number(/^([\d.]+) KB\/s$/.exec(sdLink.link)?.[1]);
 check(
-  "the link-speed test runs the firmware data-rate test and reports a plausible rate",
+  "the throughput test runs the firmware data-rate test and reports a plausible rate",
   sdLink.on &&
     sdLink.off &&
     linkKBps > 100 &&
@@ -951,7 +951,7 @@ const linkBtn = await evaluate(`
     noteAfter: document.getElementById('linkTestNote').textContent };
 `);
 check(
-  "the link-speed button works from the Test tab and reports beside itself",
+  "the throughput button works from the Test tab and reports beside itself",
   linkBtn.before.inTestTab &&
     !linkBtn.before.disabled &&
     linkBtn.before.note === "" &&
@@ -965,7 +965,7 @@ check(
   "and while it runs it names itself as the thing holding the link",
   linkBtn.during.disabled &&
     /^(measuring…|[\d.]+ KB\/s …)$/.test(linkBtn.during.pill) &&
-    /link-speed test/.test(linkBtn.during.applyNote) &&
+    /throughput test/.test(linkBtn.during.applyNote) &&
     /Measuring/.test(linkBtn.during.note),
   `${linkBtn.during.pill} | ${linkBtn.during.applyNote}`,
 );
@@ -1085,7 +1085,7 @@ check(
   sdWhileStreaming.banner.slice(0, 80) + "…",
 );
 check(
-  "the link-speed test is refused while streaming, and says why rather than just greying",
+  "the throughput test is refused while streaming, and says why rather than just greying",
   sdWhileStreaming.linkTestRoleGone &&
     sdWhileStreaming.linkTest &&
     /deliberately saturates the link/.test(sdWhileStreaming.linkTestNote) &&
@@ -4260,7 +4260,7 @@ const skip = await evaluate(`
 `);
 check(
   "a sample is skipped, with the reason, while another panel holds the link",
-  /skipped/i.test(skip.status) && /link-speed/i.test(skip.status),
+  /skipped/i.test(skip.status) && /throughput/i.test(skip.status),
   skip.status.slice(0, 90),
 );
 await send("Emulation.setTimezoneOverride", { timezoneId: "" });

@@ -308,7 +308,7 @@ export function createSdBrowser(host, opts = {}) {
     stat("capacity", "Card capacity"),
     stat("files", "Files"),
     stat("bytes", "Total size"),
-    stat("link", "Link speed"),
+    stat("link", "Link throughput"),
   );
 
   const setStat = (key, text) => {
@@ -994,7 +994,7 @@ export function createSdBrowser(host, opts = {}) {
     }
     setBusy(true);
     log.log(
-      `measuring raw link speed (${(durationMs / 1000).toFixed(0)} s, firmware data-rate test)…`,
+      `measuring raw throughput (${(durationMs / 1000).toFixed(0)} s, firmware data-rate test)…`,
     );
     try {
       const res = await client.runDataRateTest(durationMs, (bytes, ms) => {
@@ -1005,7 +1005,7 @@ export function createSdBrowser(host, opts = {}) {
       setStat("link", `${res.kBps.toFixed(1)} KB/s`);
       reportLinkSpeed(res.kBps, true);
       log.log(
-        `raw link speed: ${res.kBps.toFixed(1)} KB/s ` +
+        `raw throughput: ${res.kBps.toFixed(1)} KB/s ` +
           `(${fmtBytes(res.bytesReceived)} in ${(res.durationMs / 1000).toFixed(1)}s).`,
       );
       if (res.kBps > 0) {
@@ -1024,7 +1024,7 @@ export function createSdBrowser(host, opts = {}) {
       }
       return res;
     } catch (err) {
-      log.error(`Link speed test failed: ${err?.message ?? err}`);
+      log.error(`Throughput test failed: ${err?.message ?? err}`);
       reportLinkSpeed(null, true);
       return null;
     } finally {