Difference between revisions of "PineTime FAQ"

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'''Does the PineTime run Linux?'''
=== Does PineTime run Linux? ===


No. Please read this forum article for information about Linux on PineTime: https://forum.pine64.org/showthread.php?tid=8112
No. [https://forum.pine64.org/showthread.php?tid=8112 Please read this forum article] for information about Linux on PineTime. Also check out the article [https://lupyuen.github.io/pinetime-rust-mynewt/articles/pinetime "PineTime doesn't run Linux... But that's OK!"]


=== Why are there two versions of the Pinetab in the store? ===
=== Why can I only buy the closed version in a 3-pack, and the open version per one? ===


'''How long does it take to ship my PineTime?'''
TL:DR: The open PineTime is to develop on, The closed one only for production use, because of firmware uploads. That is why they are sold per 3.
 
In the current situation in development there are some reasons to want to be sure you only experiment with an open device. If you install the wrong firmware, your device could be bricked, until you find a way to open it, which will likely damage the device.
The idea is that if you want to develop an application for the PineTime, you will be testing it out first, and only after you know for sure your new firmware is well tested, you will install it on deployment devices. If you are in the deploy stage, having more than one PineTime is likely the point. So to prevent people from locking themselves out at the first test, it was decided to sell the closed version only as a pack of 3. Development can be done on an open device, so any issues can be easily handled.
 
=== How long does it take to ship my PineTime? ===


That depends on whether you chose for Standard or Express shipping. Standard shipping for the dev kit may take up to a few weeks.
That depends on whether you chose for Standard or Express shipping. Standard shipping for the dev kit may take up to a few weeks.


=== How do I install new software on PineTime? ===
The nRF Connect mobile app (Android and iOS) may also be used to update the firmware on your PineTime. See [https://lupyuen.github.io/pinetime-rust-mynewt/articles/cloud#download-and-test-our-pinetime-firmware "Download and Test Our PineTime Firmware"]
Also see [[Reprogramming_the_PineTime|this page to see various methods of reprogramming the devkit PineTime the wired way]].
If you have a Sealed PineTime, flash only Certified PineTime Firmware to your PineTime. If you flash non-Certified PineTime Firmware, your Sealed PineTime may be bricked permanently.
The only Certified PineTime Firmware available today is [https://github.com/JF002/Pinetime/releases/tag/0.8.2 InfiniTime 0.8.2]. Download the file "dfu-0.8.2.zip" under "Assets" and flash to PineTime with nRF Connect. Refer to the instructions here: [https://lupyuen.github.io/pinetime-rust-mynewt/articles/cloud#download-and-test-our-pinetime-firmware "Download and Test Our PineTime Firmware"]
Remember to validate the firmware after flashing: Swipe up to show the menu, tap the Ticks icon, tap "Validate"
=== My PineTime arrived, now what? ===
You should start by testing out all the features of the watch, to make sure everything works. Power it on and check the display.
PineTime is shipped with InfiniTime firmware. Press the watch button to show the clock, then swipe up on the touchscreen to reveal the menu.
On your Android phone, install the nRF Connect mobile app to sync the date and time with PineTime. See [https://lupyuen.github.io/pinetime-rust-mynewt/articles/cloud#set-pinetime-date-and-time-with-nrf-connect "Set PineTime Date and Time with nRF Connect"] (nRF Connect on iOS can't be used for setting the date and time, because it doesn't implement the GATT Time Service)
Download the latest Certified PineTime Firmware (see the previous question) and flash to PineTime with nRF Connect. Refer to the instructions here: [https://lupyuen.github.io/pinetime-rust-mynewt/articles/cloud#download-and-test-our-pinetime-firmware "Download and Test Our PineTime Firmware"]
Remember to validate the firmware after flashing: Swipe up to show the menu, tap the Ticks icon, tap "Validate"
=== What's the OS that's preinstalled on the PineTime by default? ===
PineTime ships with the open source [https://github.com/JF002/Pinetime InfiniTime firmware].


'''My PineTime arrived, now what?'''
To support firmware update and rollback, PineTime includes the open source [https://lupyuen.github.io/pinetime-rust-mynewt/articles/mcuboot MCUBoot Bootloader].


You should start by testing out all the features of the watch, to make sure everything works. You can do this using the software that was preinstalled on your device. '''Don't solder wires to the pins unless you really know how to do so safely!''' The wire that comes with the devkit already works for removing the protection and flashing code, only takes plugging it into the holes and holding it still gently. After the flash lock has been removed you can experiment with your own software or someone else's.
=== Can we use this OS or its source code? ===


Yes, [https://github.com/JF002/Pinetime InfiniTime] and the [https://lupyuen.github.io/pinetime-rust-mynewt/articles/mcuboot MCUBoot Bootloader] are open source.


'''How do I remove flash protection?'''
=== Why is the back exposed? Is it supposed to snap on? ===


The flash protection can be removed using multiple different methods. If you don't have anything except the PineTime, not even a RPi, then you have to order a programmer online, you can use a J-Link, CMSIS-DAP dongle and various other programmers. See [[Reprogramming_the_PineTime|this page to see various methods of preprogramming the PineTime]].
The back cover of the PineTime dev kit is exposed so that you can flash and debug the device with the SWD pins. The main unit and cover does not snap (lock) together. If you want to attach the back cover anyway, you can use glue or tape.


=== What hardware should I use to flash code to the PineTime? ===


'''Why can't you use ST-Link to remove nRF52 Flash Protection?'''
There are several ways you can do this, check out [[Reprogramming the PineTime]]


Because ST-Link is a High Level Adapter. It doesn't really implement all SWD functions, just a subset. For performance I think. More details in the section "Why Visual Studio Code with ST-Link (instead of nRFgo Studio with J-LINK)" in the article "Coding nRF52 with Rust and Apache Mynewt on Visual Studio Code" here: https://medium.com/@ly.lee/coding-nrf52-with-rust-and-apache-mynewt-on-visual-studio-code-9521bcba6004?source=friends_link&sk=bb4e2523b922d0870259ab3fa696c7da
=== How do I connect the PineTime to a programmer? ===


Here's how: [[PineTime devkit wiring]]


'''Since we need a low level SWD adapter like Raspberry Pi anyway, can we do everything on a Pi instead of ST-Link + Windows?'''
=== How do I set the time on PineTime? ===


Current progress with Pi and PineTime is here https://medium.com/@ly.lee/debug-rust-mynewt-firmware-for-pinetime-on-raspberry-pi-4b9ac2d093a9?source=friends_link&sk=edb508c31e43d3ec40ecd8554f3405f6
You can use either nRF Connect, custom GadgetBridge build or the proprietary Da Fit app. See [https://lupyuen.github.io/pinetime-rust-mynewt/articles/cloud#set-pinetime-date-and-time-with-nrf-connect "Set PineTime Date and Time with nRF Connect"]


=== Is there a standard agreed method of pushing OTA updates so that one could seal the PineTime dev kit nicely? ===


'''What's the OS that's preinstalled on the PineTime by default?'''
InfiniTime supports firmware updates over Bluetooth LE with the nRF Connect mobile app. See [https://lupyuen.github.io/pinetime-rust-mynewt/articles/cloud#download-and-test-our-pinetime-firmware "Download and Test Our PineTime Firmware"]


The watch, and its preinstalled OS, is built by a friend of TL. The software is proprietary and not made by Pine64 or its community. It can interact with the "Da Fit" app on Android. The dev kit contains this OS (and as a result, the flash protection) so that developers can test if all the hardware on their device is working correctly before they flash the device and start working on their own software.
=== My PineTime's screen shows garbage, how do I fix it? ===


This is usually caused by unplugging the device after it has booted, it needs to be reinitialised. To do so just restart the watch by removing power to it.


'''Can we use this OS or its source code?'''
=== I have experience developing on Arduino. How does the PineTime compare? ===


While it's not what the dev kit is for, you are of course free to use the watch with its preinstalled software as is. The preinstalled OS is proprietary, and its owner will not release the source code, so we cannot use this OS as a starting point.
To learn programming on PineTime, [https://lupyuen.github.io/pinetime-rust-mynewt/articles/cloud check out this article]


Arduino provides the Arduino IDE (or you use the avr-gcc and avrdude command-line tools) which you can use to compile and upload code to an Arduino board. The PineTime and its ARM processor doesn't have this, so you'll have to familiarize yourself with tools like GCC for ARM, and OpenOCD. Some experience with Arduino does translate over to the PineTime, especially if you've worked with LCD's, or SPI. The PineTime is at least four times faster than an Arduino Uno (even faster at certain specific workloads due to hardware acceleration), and it has 32 times more RAM and 16 times more flash storage.


'''Why is the back exposed? Is it supposed to snap on?'''
[https://github.com/lupyuen/ Lup Yuen Lee] (just call him Lup, rhymes with "Up") has written many articles on PineTime programming. [https://lupyuen.github.io/ Check out the articles here]


The back cover of the PineTime dev kit is exposed so that you can flash and debug the device with the SWD pins. The main unit and cover does not snap (lock) together. If you want to attach the back cover anyway, you can use glue or tape.
=== Can I code firmware for PineTime without an actual PineTime? ===
 
Yes, you may code PineTime Watch Faces and preview them in a web browser (thanks to WebAssembly)...


[https://lupyuen.github.io/pinetime-rust-mynewt/articles/simulator PineTime Simulator]


'''What hardware should I use to flash code to the PineTime?'''
Then flash your firmware remotely to a real PineTime via Telegram, and watch your firmware run in a live video stream...


There are several ways you can do this:
[https://github.com/lupyuen/remote-pinetime-bot/blob/master/README.md Remote PineTime]


a) Use a J-Link. These can remove flash protection as well, so you won't need a Raspberry Pi to start working on the PineTime. A cheap option for this is the J-Link EDU: https://www.segger.com/products/debug-probes/j-link/models/j-link-edu/.
=== What do I need for building PineTime firmware locally on my computer? ===


b) Use an even cheaper CMSIS-DAP dongle (sometimes called DAPLINK) from AliExpress, that too allows removing the flash protection and flashing new software using OpenOCD. Search for "CMSIS-DAP" or "DAPLINK" on AliExpress.
Most flavours of PineTime firmware (InfiniTime, Hypnos, Klok, wasp-os) will build fine on Linux (x64, Arm32, Arm64) and macOS. Just follow the instructions provided.


c) Use a Raspberry Pi with OpenOCD
Download version 9-2020-q2-update of the [https://developer.arm.com/tools-and-software/open-source-software/developer-tools/gnu-toolchain/gnu-rm/downloads Arm Embedded Toolchain arm-none-eabi-gcc]. Other versions of gcc may have problems building the firmware correctly.


d) Use a ST-Link V2 clone. Search for "ST-Link V2" on AliExpress or Amazon to buy one of these.
On Windows, install [https://docs.microsoft.com/en-us/windows/wsl/about Windows Subsystem for Linux (WSL)] and execute the build steps inside the WSL Terminal (instead of the Windows Command Prompt). USB Programmers (like ST-Link and JLink) are not supported in WSL, so use the Windows Command Prompt to flash your built firmware to PineTime.


e) Finally, you can use an STM32F103 "Blue Pill" with BMP (Black Magic Probe). Here's a nice guide for that: https://devzone.nordicsemi.com/nordic/nordic-blog/b/blog/posts/flashing-and-debugging-nrf5152-with-a-cheap-blackm
[https://github.com/lupyuen/pinetime-rust-mynewt/blob/master/README.md pinetime-rust-mynewt] firmware for PineTime supports building and flashing via the Windows Command Prompt (no need for MinGW and Docker).


=== Can I use Pinebook Pro for developing PineTime? ===


'''I have experience developing on Arduino. How does the PineTime compare?'''
Yes, use version 9-2020-q2-update of the [https://developer.arm.com/tools-and-software/open-source-software/developer-tools/gnu-toolchain/gnu-rm/downloads Arm Embedded Toolchain arm-none-eabi-gcc]. Other versions of gcc may have problems building the firmware correctly.


Arduino provides the Arduino IDE (or you use the avr-gcc and avrdude command-line tools) which you can use to compile and upload code to an Arduino board. The PineTime and its ARM processor doesn't have this, so you'll have to familiarize yourself with tools like GCC for AVR, and OpenOCD. Some experience with Arduino does translate over to the PineTime, especially if you've worked with LCD's, or SPI. The PineTime is at least four times faster than an Arduino Uno (even faster at certain specific workloads due to hardware acceleration), and it has 32 times more RAM and 16 times more flash storage.
=== What is Arm Semihosting? ===


We use the SWD (Single Wire Debug) protocol created by Arm for flashing and debugging PineTime's nRF52832 microcontroller, which contains an Arm CPU. (SWD is derived from standard JTAG, but with fewer wires) With Arm CPUs you can trigger a software breakpoint, and allow the debugger (OpenOCD) to do something really nifty: Display a message, read console input, dump out a file, even read a file. That's called Arm Semihosting. [http://www.keil.com/support/man/docs/armcc/armcc_pge1358787046598.htm More about Arm Semihosting]


'''My PineTime has the stock proprietary software on it, how do I set the time?'''
=== What is OpenOCD? ===


You can use either nRF Connect, custom GadgetBridge build or the proprietary Da Fit app.
OpenOCD is Open On-Chip Debugger. It's the software that drives your microcontroller debugger/flasher. We need it for running any kind of flashing and debugging with Pi or ST-Link. gdb talks to OpenOCD for debugging firmware. gdb also works with VSCode for debugging firmware visually. [http://openocd.org/doc-release/html/About.html#What-is-OpenOCD_003f More about OpenOCD]


Please use [https://xpack.github.io/openocd xPack OpenOCD] with PineTime. Other versions of OpenOCD seem to have problems with PineTime.


'''My PineTime's screen shows garbage, how do I fix it?'''
=== How do I remove flash protection? ===


This is usually caused by unplugging the device after it has booted, it needs to be reinitialised. To do so just restart the watch by removing power to it.
PineTime watches shipped before 20 Sep 2020 have flash protection enabled.


The flash protection can be removed using multiple different methods. If you don't have anything except the PineTime, not even a Raspberry Pi, then you have to order a programmer online: you can use a J-Link, CMSIS-DAP dongle and various other programmers. See [[Reprogramming_the_PineTime|this page to see various methods of reprogramming the PineTime]].


'''Is there a 3D model of PineTime available somewhere?'''
If your PineTime was shipped after 20 Sep 2020, you don't need to remove flash protection. They are shipped with flash protection disabled. You can flash and debug PineTime right away with ST-Link, JLink and Raspberry Pi.


Not yet.
=== Why can't you use ST-Link to remove nRF52 Flash Protection? ===


Because ST-Link is a High Level Adapter. It doesn't really implement all SWD functions, just a subset (probably to keep the price low). More details in the section "Why Visual Studio Code with ST-Link (instead of nRFgo Studio with J-LINK)" in the article [https://medium.com/@ly.lee/coding-nrf52-with-rust-and-apache-mynewt-on-visual-studio-code-9521bcba6004?source=friends_link&sk=bb4e2523b922d0870259ab3fa696c7da "Coding nRF52 with Rust and Apache Mynewt on Visual Studio Code"].


'''Is there a standard agreed method of pushing OTA updates so that one could seal the PineTime dev kit nicely?'''
=== Since we need a low level SWD adapter like Raspberry Pi anyway, can we do everything on a Pi instead of ST-Link + Windows? ===


Not yet.
Yes, Raspberry Pi works for flashing and debugging PineTime, even for removing flash protection. We have a special version of OpenOCD called OpenOCD SPI that talks to PineTime's SWD port over SPI (without bit-banging). See [https://github.com/lupyuen/pinetime-updater/blob/master/README.md PineTime Updater]


=== Is there a 3D model of PineTime available somewhere? ===


'''What is Arm Semihosting?'''
Not yet. Someone did design a cover you can snap on to keep the back shut. [https://www.thingiverse.com/thing:4172849 More details]


So we know that we use the SWD (Single Wire Debug) protocol created by Arm for flashing and debugging Arm embedded CPUs. SWD being derived from standard JTAG, but with fewer wires
=== Are there any alternatives to the wrist band provided with the PineTime? ===
With Arm CPUs you can trigger an software interrupt, and allow the debugger (OpenOCD) to do something really nifty
Display a message, read console input, dump out a file, even read a file! Thats called Arm Semihosting http://www.keil.com/support/man/docs/armcc/armcc_pge1358787046598.htm


No, but PineTime accepts standard 20mm wrist band that is widely available by a third party.


'''What is OpenOCD?'''
Note that some sellers have a different point of view on what standard is. So you should always check the fitting to make sure it looks like the one used by PineTime.
OpenOCD is Open On-Chip Debugger. It's the software that drives your microcontroller debugger/flasher. We need it for running any kind of flashing and debugging with Pi or ST-Link. gdb talks to OpenOCD for debugging firmware. And VSCode talks to gdb for debugging firmware visually. http://openocd.org/doc-release/html/About.html#What-is-OpenOCD_003f
There have been no official updates for years, the closest one is by ntfreak: https://github.com/ntfreak/openocd (My SPI fork is based on this)


=== I'm stuck. How can I get help? ===


'''Can I use Pinebook Pro for developing PineTime?'''
Chat with the PineTime Community on [[PineTime#Community|Matrix / Discord / Telegram / IRC]] (They are bridged into a single chatroom)


Arm Embedded Toolchain for Pinebook Pro is here, if anyone needs it. It's linked with dynamic libraries, so I fear it might not work on your Pinebook Pro. Hoping to save you 7 hours of painful toolchain building... https://github.com/lupyuen/pinetime-rust-mynewt/releases/tag/v1.0.5
[[Category:PineTime]]

Revision as of 13:06, 21 October 2020

Does PineTime run Linux?

No. Please read this forum article for information about Linux on PineTime. Also check out the article "PineTime doesn't run Linux... But that's OK!"

Why are there two versions of the Pinetab in the store?

Why can I only buy the closed version in a 3-pack, and the open version per one?

TL:DR: The open PineTime is to develop on, The closed one only for production use, because of firmware uploads. That is why they are sold per 3.

In the current situation in development there are some reasons to want to be sure you only experiment with an open device. If you install the wrong firmware, your device could be bricked, until you find a way to open it, which will likely damage the device. The idea is that if you want to develop an application for the PineTime, you will be testing it out first, and only after you know for sure your new firmware is well tested, you will install it on deployment devices. If you are in the deploy stage, having more than one PineTime is likely the point. So to prevent people from locking themselves out at the first test, it was decided to sell the closed version only as a pack of 3. Development can be done on an open device, so any issues can be easily handled.

How long does it take to ship my PineTime?

That depends on whether you chose for Standard or Express shipping. Standard shipping for the dev kit may take up to a few weeks.

How do I install new software on PineTime?

The nRF Connect mobile app (Android and iOS) may also be used to update the firmware on your PineTime. See "Download and Test Our PineTime Firmware"

Also see this page to see various methods of reprogramming the devkit PineTime the wired way.

If you have a Sealed PineTime, flash only Certified PineTime Firmware to your PineTime. If you flash non-Certified PineTime Firmware, your Sealed PineTime may be bricked permanently.

The only Certified PineTime Firmware available today is InfiniTime 0.8.2. Download the file "dfu-0.8.2.zip" under "Assets" and flash to PineTime with nRF Connect. Refer to the instructions here: "Download and Test Our PineTime Firmware"

Remember to validate the firmware after flashing: Swipe up to show the menu, tap the Ticks icon, tap "Validate"

My PineTime arrived, now what?

You should start by testing out all the features of the watch, to make sure everything works. Power it on and check the display.

PineTime is shipped with InfiniTime firmware. Press the watch button to show the clock, then swipe up on the touchscreen to reveal the menu.

On your Android phone, install the nRF Connect mobile app to sync the date and time with PineTime. See "Set PineTime Date and Time with nRF Connect" (nRF Connect on iOS can't be used for setting the date and time, because it doesn't implement the GATT Time Service)

Download the latest Certified PineTime Firmware (see the previous question) and flash to PineTime with nRF Connect. Refer to the instructions here: "Download and Test Our PineTime Firmware"

Remember to validate the firmware after flashing: Swipe up to show the menu, tap the Ticks icon, tap "Validate"

What's the OS that's preinstalled on the PineTime by default?

PineTime ships with the open source InfiniTime firmware.

To support firmware update and rollback, PineTime includes the open source MCUBoot Bootloader.

Can we use this OS or its source code?

Yes, InfiniTime and the MCUBoot Bootloader are open source.

Why is the back exposed? Is it supposed to snap on?

The back cover of the PineTime dev kit is exposed so that you can flash and debug the device with the SWD pins. The main unit and cover does not snap (lock) together. If you want to attach the back cover anyway, you can use glue or tape.

What hardware should I use to flash code to the PineTime?

There are several ways you can do this, check out Reprogramming the PineTime

How do I connect the PineTime to a programmer?

Here's how: PineTime devkit wiring

How do I set the time on PineTime?

You can use either nRF Connect, custom GadgetBridge build or the proprietary Da Fit app. See "Set PineTime Date and Time with nRF Connect"

Is there a standard agreed method of pushing OTA updates so that one could seal the PineTime dev kit nicely?

InfiniTime supports firmware updates over Bluetooth LE with the nRF Connect mobile app. See "Download and Test Our PineTime Firmware"

My PineTime's screen shows garbage, how do I fix it?

This is usually caused by unplugging the device after it has booted, it needs to be reinitialised. To do so just restart the watch by removing power to it.

I have experience developing on Arduino. How does the PineTime compare?

To learn programming on PineTime, check out this article

Arduino provides the Arduino IDE (or you use the avr-gcc and avrdude command-line tools) which you can use to compile and upload code to an Arduino board. The PineTime and its ARM processor doesn't have this, so you'll have to familiarize yourself with tools like GCC for ARM, and OpenOCD. Some experience with Arduino does translate over to the PineTime, especially if you've worked with LCD's, or SPI. The PineTime is at least four times faster than an Arduino Uno (even faster at certain specific workloads due to hardware acceleration), and it has 32 times more RAM and 16 times more flash storage.

Lup Yuen Lee (just call him Lup, rhymes with "Up") has written many articles on PineTime programming. Check out the articles here

Can I code firmware for PineTime without an actual PineTime?

Yes, you may code PineTime Watch Faces and preview them in a web browser (thanks to WebAssembly)...

PineTime Simulator

Then flash your firmware remotely to a real PineTime via Telegram, and watch your firmware run in a live video stream...

Remote PineTime

What do I need for building PineTime firmware locally on my computer?

Most flavours of PineTime firmware (InfiniTime, Hypnos, Klok, wasp-os) will build fine on Linux (x64, Arm32, Arm64) and macOS. Just follow the instructions provided.

Download version 9-2020-q2-update of the Arm Embedded Toolchain arm-none-eabi-gcc. Other versions of gcc may have problems building the firmware correctly.

On Windows, install Windows Subsystem for Linux (WSL) and execute the build steps inside the WSL Terminal (instead of the Windows Command Prompt). USB Programmers (like ST-Link and JLink) are not supported in WSL, so use the Windows Command Prompt to flash your built firmware to PineTime.

pinetime-rust-mynewt firmware for PineTime supports building and flashing via the Windows Command Prompt (no need for MinGW and Docker).

Can I use Pinebook Pro for developing PineTime?

Yes, use version 9-2020-q2-update of the Arm Embedded Toolchain arm-none-eabi-gcc. Other versions of gcc may have problems building the firmware correctly.

What is Arm Semihosting?

We use the SWD (Single Wire Debug) protocol created by Arm for flashing and debugging PineTime's nRF52832 microcontroller, which contains an Arm CPU. (SWD is derived from standard JTAG, but with fewer wires) With Arm CPUs you can trigger a software breakpoint, and allow the debugger (OpenOCD) to do something really nifty: Display a message, read console input, dump out a file, even read a file. That's called Arm Semihosting. More about Arm Semihosting

What is OpenOCD?

OpenOCD is Open On-Chip Debugger. It's the software that drives your microcontroller debugger/flasher. We need it for running any kind of flashing and debugging with Pi or ST-Link. gdb talks to OpenOCD for debugging firmware. gdb also works with VSCode for debugging firmware visually. More about OpenOCD

Please use xPack OpenOCD with PineTime. Other versions of OpenOCD seem to have problems with PineTime.

How do I remove flash protection?

PineTime watches shipped before 20 Sep 2020 have flash protection enabled.

The flash protection can be removed using multiple different methods. If you don't have anything except the PineTime, not even a Raspberry Pi, then you have to order a programmer online: you can use a J-Link, CMSIS-DAP dongle and various other programmers. See this page to see various methods of reprogramming the PineTime.

If your PineTime was shipped after 20 Sep 2020, you don't need to remove flash protection. They are shipped with flash protection disabled. You can flash and debug PineTime right away with ST-Link, JLink and Raspberry Pi.

Why can't you use ST-Link to remove nRF52 Flash Protection?

Because ST-Link is a High Level Adapter. It doesn't really implement all SWD functions, just a subset (probably to keep the price low). More details in the section "Why Visual Studio Code with ST-Link (instead of nRFgo Studio with J-LINK)" in the article "Coding nRF52 with Rust and Apache Mynewt on Visual Studio Code".

Since we need a low level SWD adapter like Raspberry Pi anyway, can we do everything on a Pi instead of ST-Link + Windows?

Yes, Raspberry Pi works for flashing and debugging PineTime, even for removing flash protection. We have a special version of OpenOCD called OpenOCD SPI that talks to PineTime's SWD port over SPI (without bit-banging). See PineTime Updater

Is there a 3D model of PineTime available somewhere?

Not yet. Someone did design a cover you can snap on to keep the back shut. More details

Are there any alternatives to the wrist band provided with the PineTime?

No, but PineTime accepts standard 20mm wrist band that is widely available by a third party.

Note that some sellers have a different point of view on what standard is. So you should always check the fitting to make sure it looks like the one used by PineTime.

I'm stuck. How can I get help?

Chat with the PineTime Community on Matrix / Discord / Telegram / IRC (They are bridged into a single chatroom)