It's possible I think.
Your app writes something into another characteristic to issue a request.
It can be detected by write_handler() and 2073X sends the request to another device.
After getting current status through uart, the app can get the status by notification.
Oh no . The variant has also been suggested to me a colleague.
But I thought that needs to go easier.....
I have 33 services and each service have 15 characteristics.
5 characteristics need a "update" button.
Do these 5 characteristics need to be updated independently?
If "update" doesn't happen so often, you can get all 5 status through uart and update these characteristics at once.
independently, yes to reduce the traffic.
I think i try it with one additional characteristic and write different values to see which characteristic needs an update.