Setting manufacturer data returns BLE_HS_EMSGSIZE error

[IanMcCarthy]

Hi, I'm implementing a simple server with a simple advertising packet.

Assuming advertising packet size is 31 bytes and my packed struct (advData) is 26 bytes in size (which it is), I should be able to send:

0x02, 0x01, 0x06 (set by nimble)
0x1B, 0xFF, 0x00, (24 more bytes), 0x00 (set by me)

Using: pAdvertising->setManufacturerData(std::string((char *)&advData, sizeof(advData)));

I get an BLE_HS_EMSGSIZE error and no advertising.

If I use: pAdvertising->setManufacturerData(std::string((char *)&advData, sizeof(advData) - 2));

It works and starts advertising.

Can anyone shed some light on what I'm doing wrong, please?

[IanMcCarthy]

Should anyone come across this later...

I needed to specifically call: NimBLEDevice::getAdvertising()->setName("");

Other 2 bytes are reserved for the name block, even if I didn't set one.