Large MTU?

[Mike Mitchell]

I have a device with a large MTU, and it works ok with other apps on the same device. But with RedMobile, the droid never sends the MTU exchange message like other apps do. This would be OK if it just accepted the advertised size, but it has not. So when the device tries to send it is rejected. 

This seems like a bug in RedMobile or the underlying BLE implementation to me since other apps work.  Has anyone else gotten a device with 512 byte MTU to work? 

[okhiroyuki]

Hi,

As you mentioned, RedMobile does not currently support Large MTU.
Can this be solved by adding a node that can be made to change the MTU value? Or is it more natural to automatically set the MTU value to Max512b? Please give me your opinion.

2022年2月11日金曜日 6:04:09 UTC+9 Mike Mitchell:

[Mike Mitchell]

@okhiroyuki   Thanks for letting me know. I don't think it's possible  for an existing node to do this since it's in the stack. Can you suggest how?   But it should be pretty easy to add. Yes,  you would request the highest possible, which is either 512 or 517 depending on how they define it.  Then in the  callback the actual value agreed to by the device is returned. 

It looks like you use Cordova so this might help: ble.requestMtu(device_id, mtu, [success], [failure]);

 https://githubhelp.com/don/cordova-plugin-ble-central#requestmtu?ref=https://githubhelp.com

This is a project breaker for me. How fast do you think you might be able to add that?  I would be glad to do beta testing for you. 

Thanks.