# \#parallax-inc
**URL:** https://forum.digikey.com/tag/parallax-inc/4609.md
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## [【RFID 技術討論】RFID 標籤的 ID 能修改嗎？深入解析唯讀與可寫入標籤](https://forum.digikey.com/t/rfid-rfid-id/65746)
**Author:** [@Barley\_Li](https://forum.digikey.com/u/Barley_Li)\
**Replies:** 0\
**Last updated:** [February 23, 2026, 7:07am UTC](https://forum.digikey.com/t/rfid-rfid-id/65746 "2026-02-23T07:07:34Z")
我們時常收到這樣的問題： RFID 標籤的身份識別號（ID）究竟能不能被修改？ 從多數 RFID 系統的設計來看，標籤的 ID 一般是以 序列方式分配，並在晶片製造時永久燒錄（burned-in）。查詢了許多資料，幾乎找不到可讓使用者自行重寫「標籤 ID」的情況。不過，有一些細節值得說明，能幫助你更清楚理解為何大多數 RFID 標籤幾乎不可能重覆 ID。 實例 1：Parallax 28141 — 唯讀 (read-only) R…
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## [Feedback pin issue on Parallax 900-00360 servo](https://forum.digikey.com/t/feedback-pin-issue-on-parallax-900-00360-servo/45844)
**Author:** [@00.salon.flyer](https://forum.digikey.com/u/00.salon.flyer)\
**Replies:** 2\
**Last updated:** [October 22, 2024, 4:53pm UTC](https://forum.digikey.com/t/feedback-pin-issue-on-parallax-900-00360-servo/45844 "2024-10-22T16:53:21Z")
I am able to continuously spin the Parallax 900-00360 servo using the required 50Hz control signal at 3.3VDC logic level, with the servo powered by a 6VDC supply. The ground (GND) of the 6V supply is correctly connected …
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## [How to control 555-27401 QTI line sensor?](https://forum.digikey.com/t/how-to-control-555-27401-qti-line-sensor/8551)
**Author:** [@zhaohanyun](https://forum.digikey.com/u/zhaohanyun)\
**Replies:** 1\
**Last updated:** [September 8, 2020, 3:34pm UTC](https://forum.digikey.com/t/how-to-control-555-27401-qti-line-sensor/8551 "2020-09-08T15:34:48Z")
It seems that the sensor requires manually charge and discharge the capacitor inside (see the demonstration part). This cause delay in getting immediate reading, and the reading will be more discrete than that of regular…