aci_gatt_write_char_desc() uses undocumented ACI command opcode 0xFD21

[MSing.1713]

Greetings,

There is a post explaining how the aci_gatt_write_char_desc() function should be used to enable notification events for a characteristic that may be notified by the server/peripheral.  The opcode, defined as

rq.ogf = 0x3f;
rq.ocf = 0x121;

is the 16 bit opcode 0xFD21.  The September 2025 release of AN5270 (revision 32) omits this command.

Can we get an update to the AN5270 with an explanation of this command?

Cheers

[Imen.D]

Hello @MSing.1713 

Thanks for your post.

I am checking this internally with the relevant team to clarify this topic (internal ticket number 221063)
We will provide you an update as soon as possible.

Thanks for your contribution.

(PS: ticket number 221063 is an internal tracking number and is not accessible or usable by customers).

[MSing.1713]

Cool.

I also noticed that there are two opcodes with the same description, or at least as far as I can tell.

2.6.31 ACI_GATT_WRITE_WITHOUT_RESP

2.6.44 ACI_GATT_WRITE_WITHOUT_RESP

There may be a difference somewhere in the description, but I'm not seeing it.

Thoughts?