# \#samd **URL:** https://community.sparkfun.com/tag/samd/11.md [Latest](https://community.sparkfun.com/latest.md) · [Categories](https://community.sparkfun.com/categories.md) · [Tags](https://community.sparkfun.com/tags.md) --- ## [Three out of four SAMD21 Pro RF boards won't bring up serial port](https://community.sparkfun.com/t/three-out-of-four-samd21-pro-rf-boards-wont-bring-up-serial-port/68356)
**Author:** [@thisisaus](https://community.sparkfun.com/u/thisisaus)\ **Replies:** 4\ **Last updated:** [March 20, 2026, 8:17am UTC](https://community.sparkfun.com/t/three-out-of-four-samd21-pro-rf-boards-wont-bring-up-serial-port/68356 "2026-03-20T08:17:04Z")
Hello, I have been able to deploy the transmit and receive sketches on one pro rf board. I can bring that board up in Arduino IDE and observe the serial output on both Windows 10 and Ubuntu 22.04. I have three more of t… --- ## [Brand New SAMD51 on Main Board Single - No Status Light - Bad Processor?](https://community.sparkfun.com/t/brand-new-samd51-on-main-board-single-no-status-light-bad-processor/66059)
**Author:** [@armadillon](https://community.sparkfun.com/u/armadillon)\ **Replies:** 2\ **Last updated:** [July 17, 2025, 4:08pm UTC](https://community.sparkfun.com/t/brand-new-samd51-on-main-board-single-no-status-light-bad-processor/66059 "2025-07-17T16:08:26Z")
What I have: MM Main Board Single MM SAMD51 Processor Ethernet/PoE Function Board - W5500 Digi Xbee Explorer Regulated w Xbee3 Module (u.FL version) ATP Carrier Board (I have one, but I decided the Main Board single… --- ## [SAMD51J20 bootloader](https://community.sparkfun.com/t/samd51j20-bootloader/65137)
**Author:** [@potato45](https://community.sparkfun.com/u/potato45)\ **Replies:** 5\ **Last updated:** [June 7, 2025, 4:12am UTC](https://community.sparkfun.com/t/samd51j20-bootloader/65137 "2025-06-07T04:12:48Z")
I flashed the uf2 bin bootloader using the Jlink edu and studio 7 says flash was successful. But when i plug in the usb to board. I dont see it on the device manager nor the Arduino IDE. i made a custom board using the S… --- ## [Quiic Micro](https://community.sparkfun.com/t/quiic-micro/65367)
**Author:** [@cactusjuice](https://community.sparkfun.com/u/cactusjuice)\ **Replies:** 2\ **Last updated:** [June 5, 2025, 7:01pm UTC](https://community.sparkfun.com/t/quiic-micro/65367 "2025-06-05T19:01:25Z")
Hi, I am looking into purchasing a Quiic Micro SAMD21 Development Board. I am wondering if it has pins that are interrupt capable. I couldn’t find any mention of interrupt capable pins in documentation. Any help would b… --- ## [SAMD21 Qwiic Micro, failed to kick into bootloader mode](https://community.sparkfun.com/t/samd21-qwiic-micro-failed-to-kick-into-bootloader-mode/65237)
**Author:** [@onewigglyelectron](https://community.sparkfun.com/u/onewigglyelectron)\ **Replies:** 6\ **Last updated:** [May 24, 2025, 9:58pm UTC](https://community.sparkfun.com/t/samd21-qwiic-micro-failed-to-kick-into-bootloader-mode/65237 "2025-05-24T21:58:40Z")
Have been working on this QWIIC Micro board, I have 2 but one I am giving to a friend to use. Of the two, one has stop responding on the device driver window. I no longer see it as either UF2 or regular device as a compo… --- ## [MicroMod SAMD51 Processor Bootloader Code](https://community.sparkfun.com/t/micromod-samd51-processor-bootloader-code/63166)
**Author:** [@Alexander\_Weber](https://community.sparkfun.com/u/Alexander_Weber)\ **Replies:** 5\ **Last updated:** [February 5, 2025, 2:50pm UTC](https://community.sparkfun.com/t/micromod-samd51-processor-bootloader-code/63166 "2025-02-05T14:50:34Z")
I am not able to build a bootloader successfuly with latest sources from https://github.com/adafruit/uf2-samdx1 nor any older one… I’d like to have the improvements of a newer build / release, beacuse sometimes the fl… --- ## [SAMD21 Pro Rf LoRa GPIO not working](https://community.sparkfun.com/t/samd21-pro-rf-lora-gpio-not-working/61068)
**Author:** [@kefecik](https://community.sparkfun.com/u/kefecik)\ **Replies:** 6\ **Last updated:** [January 11, 2025, 8:29pm UTC](https://community.sparkfun.com/t/samd21-pro-rf-lora-gpio-not-working/61068 "2025-01-11T20:29:52Z")
I have 2 SAMD21 Pro Rf LoRa modules with antennas and the given transmitter receiver sketch is working. I am trying to get a digital on off signal working (specifically D2 on the board) but its not working. The onboard L… --- ## [Redboard turbo not recognized except in bootloader mode](https://community.sparkfun.com/t/redboard-turbo-not-recognized-except-in-bootloader-mode/59353)
**Author:** [@aocole](https://community.sparkfun.com/u/aocole)\ **Replies:** 4\ **Last updated:** [July 24, 2024, 5:40pm UTC](https://community.sparkfun.com/t/redboard-turbo-not-recognized-except-in-bootloader-mode/59353 "2024-07-24T17:40:34Z")
I bought a redboard turbo that doesn’t want to program. When I plug it in it doesn’t show up as a com port nor as a circuitpython disk. If I double-click the reset button to put it in bootloader mode then it will show up… --- ## [SAMD21G Mini built-in LED: Blink sketch](https://community.sparkfun.com/t/samd21g-mini-built-in-led-blink-sketch/47671)
**Author:** [@element](https://community.sparkfun.com/u/element)\ **Replies:** 2\ **Last updated:** [July 7, 2024, 10:05pm UTC](https://community.sparkfun.com/t/samd21g-mini-built-in-led-blink-sketch/47671 "2024-07-07T22:05:20Z")
My SAMD21G mini breakout is behaving strangely. To debug it, I uploaded the standard “Blink” sketch, but I don’t see anything flashing. “Blink” uses a LED\_BUILTIN variable to define the LED pin. I assume the SAMD21 has a… --- ## [SAMD51 thing plus isn't detected by PC.](https://community.sparkfun.com/t/samd51-thing-plus-isnt-detected-by-pc/47481)
**Author:** [@fuse\_pie39](https://community.sparkfun.com/u/fuse_pie39)\ **Replies:** 1\ **Last updated:** [May 28, 2024, 3:16am UTC](https://community.sparkfun.com/t/samd51-thing-plus-isnt-detected-by-pc/47481 "2024-05-28T03:16:39Z")
I recently ordered a Thing Plus with the SAMD51, I cant get it to be detected in Windows’s device manager and by a raspberry pi (I would’ve tried macOS if I had a compatible cable ). When I plug the board it fades the bl… --- ## [Powering a Qwiic Micro SAMD21E device (new)](https://community.sparkfun.com/t/powering-a-qwiic-micro-samd21e-device-new/47337)
**Author:** [@doctorwho8](https://community.sparkfun.com/u/doctorwho8)\ **Replies:** 1\ **Last updated:** [April 26, 2024, 11:00pm UTC](https://community.sparkfun.com/t/powering-a-qwiic-micro-samd21e-device-new/47337 "2024-04-26T23:00:28Z")
Hello! Okay, a revised question to ask: I have here a Qwiic Micro SAMD21E device, and on its back are two lines they are marked with a plus sign and a negative one. Ideally a SMT based connector for the standard LiPo g… --- ## [SparkFun Qwiic Micro (SAMD21E) no longer recognized by computer](https://community.sparkfun.com/t/sparkfun-qwiic-micro-samd21e-no-longer-recognized-by-computer/47157)
**Author:** [@mrmugles](https://community.sparkfun.com/u/mrmugles)\ **Replies:** 3\ **Last updated:** [March 27, 2024, 11:21pm UTC](https://community.sparkfun.com/t/sparkfun-qwiic-micro-samd21e-no-longer-recognized-by-computer/47157 "2024-03-27T23:21:27Z")
i was trying to code two arduinos at the same time so i plugged them both in, but then the SparkFun Qwiic Micro (SAMD21E) stops responding to everything, i cant recognize, connect or upload, and when i press the reset bu… --- ## [SAMD51 Thing Plus C and SWD programming](https://community.sparkfun.com/t/samd51-thing-plus-c-and-swd-programming/47005)
**Author:** [@rrainey](https://community.sparkfun.com/u/rrainey)\ **Replies:** 1\ **Last updated:** [March 22, 2024, 7:29pm UTC](https://community.sparkfun.com/t/samd51-thing-plus-c-and-swd-programming/47005 "2024-03-22T19:29:33Z")
I seem stuck trying to load a custom bootloader via a J-Link Edu interface using SWD. I routinely reprogram SAMD21 projects using Segger’s J-Link Edu and Microchip Studio. When I first tried this on the SAMD51 Thing Plus… --- ## [Thing Plus bootloader source?](https://community.sparkfun.com/t/thing-plus-bootloader-source/42820)
**Author:** [@vynce](https://community.sparkfun.com/u/vynce)\ **Replies:** 11\ **Last updated:** [March 22, 2024, 7:25pm UTC](https://community.sparkfun.com/t/thing-plus-bootloader-source/42820 "2024-03-22T19:25:14Z")
Are Sparkfun’s samd UF2 bootloader source modifications published anywhere? There are bootloader binaries for Sparkfun’s samd boards here: https://github.com/sparkfun/Arduino\_Boa … ers/SAMD51 The original samd UF2 boot… --- ## [Thing+ Bootloader "Magic Reset" Address Doesn't Match Chip Definition](https://community.sparkfun.com/t/thing-bootloader-magic-reset-address-doesnt-match-chip-definition/42008)
**Author:** [@shalebridge](https://community.sparkfun.com/u/shalebridge)\ **Replies:** 8\ **Last updated:** [March 22, 2024, 7:24pm UTC](https://community.sparkfun.com/t/thing-bootloader-magic-reset-address-doesnt-match-chip-definition/42008 "2024-03-22T19:24:20Z")
I was trying unsuccessfully to enter bootloader mode through software using: #define DOUBLE\_TAP\_MAGIC 0xf01669ef #define BOOT\_DOUBLE\_TAP\_ADDRESS (HSRAM\_ADDR + HSRAM\_SIZE - 4) \*(volatile uint32\_t\*)BOOT\_… --- ## [SAMD21-MINI standby current way too high](https://community.sparkfun.com/t/samd21-mini-standby-current-way-too-high/47128)
**Author:** [@openem](https://community.sparkfun.com/u/openem)\ **Replies:** 1\ **Last updated:** [March 19, 2024, 12:00am UTC](https://community.sparkfun.com/t/samd21-mini-standby-current-way-too-high/47128 "2024-03-19T00:00:28Z")
i’ve written a program that puts the SAMD21 into a low-power suspend mode, where i then wakeup with a button press… running that program on microchip’s SAMD21 XPLAINED board, my suspend current comes at ~3uA – consisten… --- ## [powering SAMD21 Mini through VCC](https://community.sparkfun.com/t/powering-samd21-mini-through-vcc/47112)
**Author:** [@openem](https://community.sparkfun.com/u/openem)\ **Replies:** 1\ **Last updated:** [March 14, 2024, 8:16pm UTC](https://community.sparkfun.com/t/powering-samd21-mini-through-vcc/47112 "2024-03-14T20:16:40Z")
is it possible to power my SAMD21 by supplying 3.3V to VCC – assuming i do NOT have the USB plugged in??? there is also a reference to a USB\_HOST\_EN pin in the docs and schematics… can’t find the pin on the board… and d… --- ## [SparkFun SAMD21 Pro RF not connecting to Windows 11](https://community.sparkfun.com/t/sparkfun-samd21-pro-rf-not-connecting-to-windows-11/46146)
**Author:** [@Craig59715](https://community.sparkfun.com/u/Craig59715)\ **Replies:** 2\ **Last updated:** [February 7, 2024, 5:43pm UTC](https://community.sparkfun.com/t/sparkfun-samd21-pro-rf-not-connecting-to-windows-11/46146 "2024-02-07T17:43:37Z")
Using Arduino IDE 1.8.19 on my Windows 11 (up to date version) running on my HP Envy (intel i7) , I have not been able to properly connect the SparkFun SAMD21 Pro RF in order to upload a sketch. The PORT is ghosted on th… --- ## [SAMD51 Thing Pluse Bootloader cannot load code larger than 496k](https://community.sparkfun.com/t/samd51-thing-pluse-bootloader-cannot-load-code-larger-than-496k/46880)
**Author:** [@robert-hh](https://community.sparkfun.com/u/robert-hh)\ **Replies:** 3\ **Last updated:** [February 1, 2024, 9:38pm UTC](https://community.sparkfun.com/t/samd51-thing-pluse-bootloader-cannot-load-code-larger-than-496k/46880 "2024-02-01T21:38:32Z")
The bootloader seems to refuse loading code in address ranges \>= 0x80000. If the binary size of the code exceeds 496k, the loading address exceeds 0x80000 and the code will not run. The code can be loaded successfully us… --- ## [Powering a Qwiic Micro SAMD21E device](https://community.sparkfun.com/t/powering-a-qwiic-micro-samd21e-device/46354)
**Author:** [@doctorwho8](https://community.sparkfun.com/u/doctorwho8)\ **Replies:** 7\ **Last updated:** [October 24, 2023, 1:58pm UTC](https://community.sparkfun.com/t/powering-a-qwiic-micro-samd21e-device/46354 "2023-10-24T13:58:09Z")
Hello! I have here one of the devices described in the title. I see on it six locations and of them, two are marked for power. That is one is for 3.3v and one for Ground. I guess what I am askling is can this device be … --- ## [SAMD51 Thing Plus Arduino Cache Error](https://community.sparkfun.com/t/samd51-thing-plus-arduino-cache-error/46341)
**Author:** [@batten44](https://community.sparkfun.com/u/batten44)\ **Replies:** 4\ **Last updated:** [October 12, 2023, 2:12pm UTC](https://community.sparkfun.com/t/samd51-thing-plus-arduino-cache-error/46341 "2023-10-12T14:12:46Z")
I couldn’t get the ATSAM51 Thing Plus Sparkfun board to work with the Arduino IDE 2.2.1. I followed the instructions on the Sparkfun website but got the following error: Invalid FQBN: getting build properties for board … --- ## [Try again: SAMD21 disconnecting from MacOSX after upload](https://community.sparkfun.com/t/try-again-samd21-disconnecting-from-macosx-after-upload/46170)
**Author:** [@hdtodd](https://community.sparkfun.com/u/hdtodd)\ **Replies:** 2\ **Last updated:** [September 12, 2023, 6:30pm UTC](https://community.sparkfun.com/t/try-again-samd21-disconnecting-from-macosx-after-upload/46170 "2023-09-12T18:30:53Z")
I’ve posted about this issue before and had no responses, but I’ll try again with more information after fresh installs. \[ viewtopic.php?f=117&t=59727&p=241894&hi … sx#p241875 \] I’m able to compile code for the SAMD21 P… --- ## [Is this SAMD21 dead?](https://community.sparkfun.com/t/is-this-samd21-dead/46184)
**Author:** [@hdtodd](https://community.sparkfun.com/u/hdtodd)\ **Replies:** 2\ **Last updated:** [September 12, 2023, 5:46pm UTC](https://community.sparkfun.com/t/is-this-samd21-dead/46184 "2023-09-12T17:46:45Z")
Following up on my prior posts. SAMD21 #1 will not go into bootloader mode with the button press. It will upload code from the 2.2.1 IDE but disconnects from the USB-serial port and kills the device driver on my MacOSX … --- ## [Clearing SAMD21 memory without IDE](https://community.sparkfun.com/t/clearing-samd21-memory-without-ide/46171)
**Author:** [@hdtodd](https://community.sparkfun.com/u/hdtodd)\ **Replies:** 1\ **Last updated:** [September 11, 2023, 12:40pm UTC](https://community.sparkfun.com/t/clearing-samd21-memory-without-ide/46171 "2023-09-11T12:40:14Z")
In trying to debug my MacOSX-SAMD upload issue, I compiled and uploaded ADKTerminalTest to the SAMD. The SAMD code works, but it disconnects the USB-serial port after typing to the Mac over the serial port. That means … --- ## [SAMD21 Pro RF Point to Point Example Sketch Help](https://community.sparkfun.com/t/samd21-pro-rf-point-to-point-example-sketch-help/46076)
**Author:** [@Pin2Hot](https://community.sparkfun.com/u/Pin2Hot)\ **Replies:** 3\ **Last updated:** [August 29, 2023, 8:21pm UTC](https://community.sparkfun.com/t/samd21-pro-rf-point-to-point-example-sketch-help/46076 "2023-08-29T20:21:04Z")
Hello, I have two Sparkfun SAMD21 Pro RF boards and I’m simply trying to get the Hookup Guide point to point example to function. One is running the Samd21\_PRF\_Client sketch and the other Samd21\_PRF\_Server. For whatever… --- ## [SAMD21 Pro RF-Lora Digital Pin access in C](https://community.sparkfun.com/t/samd21-pro-rf-lora-digital-pin-access-in-c/45878)
**Author:** [@pkdeveloper](https://community.sparkfun.com/u/pkdeveloper)\ **Replies:** 2\ **Last updated:** [July 7, 2023, 6:10am UTC](https://community.sparkfun.com/t/samd21-pro-rf-lora-digital-pin-access-in-c/45878 "2023-07-07T06:10:46Z")
I feel like an idiot asking this, but: How are digital pins accessed in C code in the arduino IDE? #define TESTSWITCH D4 …yields ‘D4’ was not declared in this scope. I’m modifying the RadioHead (Paul S’s) simple clie… --- ## [Low volatge from 3.3v pin when using battery (SAMD51 Thing Plus)](https://community.sparkfun.com/t/low-volatge-from-3-3v-pin-when-using-battery-samd51-thing-plus/45671)
**Author:** [@dumpsterlord](https://community.sparkfun.com/u/dumpsterlord)\ **Replies:** 2\ **Last updated:** [June 1, 2023, 12:56pm UTC](https://community.sparkfun.com/t/low-volatge-from-3-3v-pin-when-using-battery-samd51-thing-plus/45671 "2023-06-01T12:56:52Z")
I’m trying to power a BMP280(3.3v) pressure sensor on battery, it works fine when plugged in with the battery attached. If I detach it from usb with the batt plugged in it continues to run fine. If I try to start it on j… --- ## [SAMD51 with Adafruit BNO085](https://community.sparkfun.com/t/samd51-with-adafruit-bno085/45617)
**Author:** [@silentscreams](https://community.sparkfun.com/u/silentscreams)\ **Replies:** 1\ **Last updated:** [May 23, 2023, 3:28pm UTC](https://community.sparkfun.com/t/samd51-with-adafruit-bno085/45617 "2023-05-23T15:28:32Z")
Hi. I am trying to get an Adafruit BNO085 IMU working with the Sparkfun SAMD51 Thing Plus. I have all the libraries and dependencies loaded, the IDE recognizes the board and port. I can compile and upload code (in bootl… --- ## [Precision and stability of external 32.768kHz crystal of the DEV-13664](https://community.sparkfun.com/t/precision-and-stability-of-external-32-768khz-crystal-of-the-dev-13664/45584)
**Author:** [@GoiM](https://community.sparkfun.com/u/GoiM)\ **Replies:** 1\ **Last updated:** [May 15, 2023, 10:49pm UTC](https://community.sparkfun.com/t/precision-and-stability-of-external-32-768khz-crystal-of-the-dev-13664/45584 "2023-05-15T22:49:47Z")
Hi all, I would be interested if there is more detailed information availiable on the external 32.768kHz crystal of the DEV-13664. The BOM only states: "32.768kHz: Various standard crystals. Proven footprints. " Is th… --- ## [Hardware serial connection on SAMD51 thing plus help?](https://community.sparkfun.com/t/hardware-serial-connection-on-samd51-thing-plus-help/45523)
**Author:** [@blodnose](https://community.sparkfun.com/u/blodnose)\ **Replies:** 3\ **Last updated:** [May 2, 2023, 4:55pm UTC](https://community.sparkfun.com/t/hardware-serial-connection-on-samd51-thing-plus-help/45523 "2023-05-02T16:55:08Z")
Hello I want to connect the SAMD51 thing plus with the SOMO-II mp3 player. But i simply dont know how to do that. The SOMO-II library suggests using a connection called Serial1, but i dont know where the Serial1 is on … [Next page](https://community.sparkfun.com/tag/samd/11.md?match_all_tags=true&page=1&tags%5B%5D=samd)