Difference between write with/without response for Android and iOS

Kevin Huang1

Prodigy 20 points

Other Parts Discussed in Thread: CC2540

Hi,

I am working with CC2540 and experience the following:

1) Android -> all the write was using "Write_Type_No_Response" and seems to be working

2) iOS -> most of the write (other than OAD) requires "CBCharacteristicWriteWithResponse" to work. if using "

CBCharacteristicWriteWithoutResponse", the chip doesn't do any thing.

Anyone know what the problem is?

Is it just iOS 7 OS restriction?

Thanks

over 11 years ago

0 Willis1 over 11 years ago

TI__Genius 17975 points

I don't know the exact issue, but I believe that iOS enforces the GATT permissions. Meaning that a characteristic must explicitly have permissions for a writeWithoutResponse message to be used. If not, it will not allow you to use it and you must use a WriteWithResponse. This might be the root cause of your issue.

0 Kevin Huang1 over 11 years ago in reply to Willis1

Prodigy 20 points

How do I set writeWithoutResponse in GATT in CC2540?

The default is writeWithResponse I assume, because currently our code doesn't explicitly define write_type?

Thanks

0 Kevin Lockwood over 11 years ago in reply to Kevin Huang1

Expert 1035 points

I have tested trying to writing to a GATT attribute that is set for GATT_PROP_WRITE_NO_RSP but I see that same as you. I think this is an iOS7 issue.

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Difference between write with/without response for Android and iOS