Time sync with GBD-H1000

[nickapos]

I installed the app on a raspberry pi I have and when I am trying to sync my GBD-H1000 I am getting the following.

2025-09-15 14:53:46,743 gshock_api.logger INFO: ('✅ Found: CASIO GBD-H1000 (FE:83:32:49:37:11)',)
2025-09-15 14:53:56,852 gshock_api.logger INFO: ("Characteristics map initialized: {'26eb002c-b012-49a8-b1f8-394fb2032b0f': '26eb002c-b012-49a8-b1f8-394fb2032b0f', '26eb0030-b012-49a8-b1f8-394fb2032b0f': '26eb0030-b012-49a8-b1f8-394fb2032b0f', '26eb0024-b012-49a8-b1f8-394fb2032b0f': '26eb0024-b012-49a8-b1f8-394fb2032b0f', '26eb002d-b012-49a8-b1f8-394fb2032b0f': '26eb002d-b012-49a8-b1f8-394fb2032b0f', '26eb0023-b012-49a8-b1f8-394fb2032b0f': '26eb0023-b012-49a8-b1f8-394fb2032b0f', '00002a07-0000-1000-8000-00805f9b34fb': '00002a07-0000-1000-8000-00805f9b34fb'}",)
2025-09-15 14:53:59,556 gshock_api.logger INFO: ('Connected to CASIO GBD-H1000 ()',)
2025-09-15 14:53:59,954 gshock_api.logger INFO: ('Unknown key: 61',)
2025-09-15 14:54:10,428 gshock_api.logger INFO: ('Time set at 2025-09-15 14:54:10.427767 on CASIO GBD-H1000',)

The watch itself reports sync as failed. Sometimes I do not even get the log above. I get a connection failed message right away.

[izivkov]

OK,great watch, BTW. I don't have this watch, so let me ask a few questions to try to narrow it down. 1. The obvious question is: CASIO GBD-H1000 watch has built-in GPS, so what is the advantage of using the app to sync time, when the GPS can be used? 2. Even if the watch reports an error, is the time actually set? If you change the time on the watch manually, and then use this software to set the time, is the time set correctly on the watch? 3, Can the watch be set using the `Casio G-Shock Smart Sync` Android app? This will give us an indication if the problem can be resolved by carefully duplicating what the app does. I am not familiar with this watch. I have listed it as "Partly supported" because somebody has reported that the app can be used to set time for this watch, but I cannot verify. So let me know the answers to these 3 questions, and we can proceed from there. Ivo

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On Mon, Sep 15, 2025 at 1:24 PM Nick Apostolakis ***@***.***> wrote: *nickapos* created an issue (izivkov/GShockTimeServer#26) <#26> I installed the app on a raspberry pi I have and when I am trying to sync my GBD-H1000 I am getting the following. 2025-09-15 14:53:46,743 gshock_api.logger INFO: ('✅ Found: CASIO GBD-H1000 (FE:83:32:49:37:11)',) 2025-09-15 14:53:56,852 gshock_api.logger INFO: ("Characteristics map initialized: {'26eb002c-b012-49a8-b1f8-394fb2032b0f': '26eb002c-b012-49a8-b1f8-394fb2032b0f', '26eb0030-b012-49a8-b1f8-394fb2032b0f': '26eb0030-b012-49a8-b1f8-394fb2032b0f', '26eb0024-b012-49a8-b1f8-394fb2032b0f': '26eb0024-b012-49a8-b1f8-394fb2032b0f', '26eb002d-b012-49a8-b1f8-394fb2032b0f': '26eb002d-b012-49a8-b1f8-394fb2032b0f', '26eb0023-b012-49a8-b1f8-394fb2032b0f': '26eb0023-b012-49a8-b1f8-394fb2032b0f', '00002a07-0000-1000-8000-00805f9b34fb': '00002a07-0000-1000-8000-00805f9b34fb'}",) 2025-09-15 14:53:59,556 gshock_api.logger INFO: ('Connected to CASIO GBD-H1000 ()',) 2025-09-15 14:53:59,954 gshock_api.logger INFO: ('Unknown key: 61',) 2025-09-15 14:54:10,428 gshock_api.logger INFO: ('Time set at 2025-09-15 14:54:10.427767 on CASIO GBD-H1000',) The watch itself reports sync as failed. Sometimes I do not even get the log above. I get a connection failed message right away. — Reply to this email directly, view it on GitHub <#26>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AA7M37XPKYVHSS6XHUCBHZL3S3Y3PAVCNFSM6AAAAACGSDS7TSVHI2DSMVQWIX3LMV43ASLTON2WKOZTGQYTQOBUGYYDSMQ> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[nickapos]

I think I am the one who have used the android app to do time sync in the past. My Android phone is a bit old so I don’t use it much these days. Back when I tested it, it managed to set the time.

I will need to do some additional test to see if the time is wrong if I do a sync with the pi if it is corrected.

GPS time sync is an option but it can not be used indoors, that is why BT is the first option when it comes to time sync.

I will do a few more tests and come back to you with more details tomorrow.

[izivkov]

Sounds good, thanks!

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On Mon, Sep 15, 2025, 9:31 PM Nick Apostolakis ***@***.***> wrote: *nickapos* left a comment (izivkov/GShockTimeServer#26) <#26 (comment)> I think I am the one who have used the android app to do time sync in the past. My Android phone is a bit old so I don’t use it much these days. Back when I tested it, it managed to set the time. I will need to do some additional test to see if the time is wrong if I do a sync with the pi if it is corrected. GPS time sync is an option but it can not be used indoors, that is why BT is the first option when it comes to time sync. I will do a few more tests and come back to you with more details tomorrow. — Reply to this email directly, view it on GitHub <#26 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AA7M37WL7EEVHBHTM4AD2VD3S5R57AVCNFSM6AAAAACGSDS7TSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTEOJUGUZDGOBXGI> . You are receiving this because you commented.Message ID: ***@***.***>

[nickapos]

Ok, i did 2 tests. I changed the time manually, and did a sync. That is when i got this:

2025-09-16 08:38:08,108 gshock_api.logger INFO: ('✅ Found: CASIO GBD-H1000 (FE:83:32:49:37:11)',)
2025-09-16 08:38:20,662 gshock_api.logger INFO: ('[GShock Connect] Connection failed: ',)
2025-09-16 08:38:20,690 gshock_api.logger INFO: ('Failed to connect',)
2025-09-16 08:38:21,690 gshock_api.logger INFO: ('Waiting for Connection...',)

This was a time sync failure. After this, i clicked unpair and tried again, and in this second time, i got

2025-09-16 08:38:44,909 gshock_api.logger INFO: ('✅ Found: CASIO GBD-H1000 (EE:83:D1:31:37:11)',)
2025-09-16 08:38:46,801 gshock_api.logger INFO: ("Characteristics map initialized: {'26eb002c-b012-49a8-b1f8-394fb2032b0f': '26eb002c-b012-49a8-b1f8-394fb2032b0f', '26eb0024-b012-49a8-b1f8-394fb2032b0f': '26eb0024-b012-49a8-b1f8-394fb2032b0f', '26eb002d-b012-49a8-b1f8-394fb2032b0f': '26eb002d-b012-49a8-b1f8-394fb2032b0f', '26eb0023-b012-49a8-b1f8-394fb2032b0f': '26eb0023-b012-49a8-b1f8-394fb2032b0f', '26eb0030-b012-49a8-b1f8-394fb2032b0f': '26eb0030-b012-49a8-b1f8-394fb2032b0f', '00002a07-0000-1000-8000-00805f9b34fb': '00002a07-0000-1000-8000-00805f9b34fb'}",)
2025-09-16 08:38:47,281 gshock_api.logger INFO: ('Connected to CASIO GBD-H1000 ()',)
2025-09-16 08:38:49,482 gshock_api.logger INFO: ('Time set at 2025-09-16 08:38:49.474280 on CASIO GBD-H1000',)
2025-09-16 08:38:49,529 gshock_api.logger INFO: ("UnknownIO onReceived: bytearray(b'G\\x01')",)

The watch said that sync failed, but the time was corrected. So this second attempt was successful. I have the feeling that it tries to read/write more than just the time and that additional part is what is marked as failure.

[nickapos]

One other thing I noticed, it seems that this watch is permanently connected to the phone similarly to ecb-20
When I pair it to the phone it appears in the paired devices list similarly to ecb-20.
If there is no established pairing then Bluetooth time sync does not work at all. It says that it is unavailable.
What works partially is that if you try pairing with the Roi, then it will sync the time but the pairing itself will fail.

[izivkov]

So, it basically can sync. The first connection error is not unusual, it can happen with BLE connection, but it is not common.

What you describe in your second mail is normal for your watch. I have the DW-H5600 and it behaves exactly the same way - tries to connect continuously and needs to be paired to a specific device the first time. It will not connect to other devices, unlike the GW-B5600 for example. I call these watches "always connected", and I used to not letting them connect to the app because they interfere with other watches trying to connect. This app was designed for watches which connect a few times per day to set their time, not all the time. However, I have modified the ESP32 project to accept one connection every 6 hours, so these watches can set their time, but do not interfere with other watches. I will also change this project to do the same.

Regards,
Ivo

[nickapos]

I have the feeling that unless it is fully paired with the raspberry pi, it won’t reconnect on its own for a time sync.
I will have to initiate the connection.
Will the change of the esp32 project help with that?
So it recognises the original connection as valid and then allow for a connection every few hours?

[izivkov]

@nickapos OK, I have updated the code to allow for always-connected watches like the GBD-H100 to connect once every 6 hours.

So here's how to use it:

1. Pair your watch to the Pi. After pairing, it should connect and update the time.
2. After 6 hours, should be able to connect again. It maybe that the watch would have to be moved.

This is about the best we can do. I understand now why you asked me if you need to pair your watch if you had more than one ESP32 at different locations. Yes, this watch needs to be paired to a particular device. Maybe this is done for security reasons.

Frankly, for this advanced watch, I would just use the GPS for time sync. This app was not really designed for always-connected watches.

Regards,
Ivo