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I recently bought a few USB 3.0 SD card readers, and they ignore the SD card's write protect switch (lock protect tab). I performed the testing in Windows.

I doubt it matters, but the card readers are USB Type A, Type C, and combo Type A and Type C.

Is this now typical, or are such SD card readers likely flawed?

All of my USB 2.0 Type A SD card readers respect the SD card's write protect switch, but those readers are all at least 5 years old. So I'm not sure if what's typical has changed, or there is something else going on (bad batch of readers, bad brand, or other).

RockPaperLz- Mask it or Casket
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    Research: [the switch is purely mechanical](https://superuser.com/a/354497/432690). – Kamil Maciorowski Aug 16 '22 at 05:43
  • @KamilMaciorowski Correct... the switch is mechanical, but historically the host honours the switch's position. In this case, I'm not sure if the host is the card reader or the OS, or both. – RockPaperLz- Mask it or Casket Aug 16 '22 at 05:53
  • @KamilMaciorowski Absolutely, and my question is asking whether or not it is now typical for SD card readers to ignore the switch. – RockPaperLz- Mask it or Casket Aug 16 '22 at 06:01
  • "*None of my USB 2.0 Type A SD card readers exhibit this behaviour*" -- Meaning they do respect the switch? FWIW micro-SD cards do not even have a switch, so perhaps it's now deemed a non-essential feature on full-sized card readers? "*I'm not sure if the host is the card reader or the OS, or both*" -- It's a processing chain. The card reader would first have to sense the switch position, and then pass that information to the computer. Aren't you claiming that you have some readers that do sense the switch, and some that don't? – sawdust Aug 16 '22 at 08:21
  • @sawdust Yes, the USB 2.0 SD card readers I have all respect the switch. Yes, I'm noticing that all my USB 2.0 SD card readers respect the switch, but none of my new USB 3.0 SD card readers respect the switch. Not sure if I got a bad bunch, a bad brand, or if what's now typical has changed (hence my question). – RockPaperLz- Mask it or Casket Aug 16 '22 at 08:52

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