Bangle.js2 not quite usable

[pavelmachek]

Bangle.js2 not quite usable

adafruit-circuitpython-espruino_banglejs2-en_US-10.2.1.espruino.zip

Web page is scary

CircuitPython is not quite usable on Bangle.js2. First, web page is scary/confused:

https://circuitpython.org/board/espruino_banglejs2/

Says:

On nRF boards, CircuitPython 8.2.0 and later require UF2 bootloader version 0.6.1 or later. Older bootloaders cannot load the firmware. See Update UF2 Bootloader below.

That's confusing. UF2 is not actually used on Bangle.js2, and there's no "update uf2... below" section.

Instead, firmware can be updated using web IDE (but not banglejs app loader, AFAICT).

Installation erases existing data on watch, perhaps that would be worth mentioning on the web page.

Watchdog kills device

Good news is, that CircuitPython is able to boot on the watch. Bad news is, it is not quite usable. Text with very small font explaining that repl is being entered. I tried to connect to repl over bluetooth-LE, but failed... and in any case watchdog reboots the watch within a minute, so repl probably would not be usable.

(Actually, for watch, it would be very nice if display showed battery status and time by default, because otherwise... it will be very difficult to use the device as watch :-) ).

[dhalbert]

The bangle port was done by @tannewt, but a while ago. Scott, any comments on this?

The serial device for BLE workflow is not working well right now. This appears to be true across most devices.

The UF2 warning is a general one for all nordic boards. I'm not sure we have an escape hatch on circuitpython.org for suppressing that for certain boards. Maybe if bootloader_id: is empty.

[tannewt]

I was using the bangle.js 2 of my watch for a while but a failed update locked me out IIRC. It's been a few years since I used it. Getting the REPL going first would be a good start and can be done on any nrf.

My code.py from it is here:
https://gist.github.com/tannewt/6240315a92746796f663d80289c4f4c9

Maybe the board_background_task mechanic has changed. Looks like it used to feed the watchdog:

circuitpython/ports/nordic/boards/espruino_banglejs2/board.c

Line 57 in 30d7add

void board_background_task(void) {

I don't have time to fix this myself but hope those clues help get it going.

[pavelmachek]

Thanks for pointers. I only have Bangle.js 2 (and no debug cable). You mentioned "update locked you out" -- does that mean system is a bit too easy to brick? In particular, if I get watchdog fed too often, is it possible that I won't be able to reboot into bootloader -- and thus unable to go back to Espruino?

[pavelmachek]

Hmm. I see there are old binaries available on s3 -- such as adafruit-circuitpython-espruino_banglejs2-en_US-8.2.7.espruino.zip . If this used to work, could I simply flash one of the old releases to get REPL + watchdog ? Would there be recommended release?

[dhalbert]

Try the first and last of each major release, like 8.0.0 and 8.2.7, 9.0.0 and 9.2.9, and 10.0.0, and see if you get anywhere. The older ones if they worked were good for their time! Lots of code and projects done with old releases.

[pavelmachek]

So I tried these. 10.2.1 keeps rebooting after watchdog, others seem to be behaving the same way, code runs (I seen "hello world" at least once), there's periodic vibrations, but I see nothing on hcitool lescan and can't connect from the IDE. Screen says "press any key to enter REPL", but I don't know how to press a key -- button does not work -- so I'm stuck.

adafruit-circuitpython-espruino_banglejs2-en_US-10.2.1.espruino.zip : watchdog kills it, could not get REPL to work

adafruit-circuitpython-espruino_banglejs2-en_US-8.2.10.espruino.zip : keeps running, periodic vibrations (no watchdog problem), but see nothing at scan, no REPL?

adafruit-circuitpython-espruino_banglejs2-en_US-9.2.9.espruino.zip : keeps running with periodic vibrations, nothing at scan

adafruit-circuitpython-espruino_banglejs2-en_US-8.1.0.espruino.zip : keeps running with periodic vibrations, nothing at scan