Write Long using MCP 3.6

[c cook]

I have a 32 byte string to read and write using SD110. In the MCP I can read (using read long) the whole string without any problems. When I try to use write long, MCP times out after about 30 seconds with the error message "Could not update handle (0x0013) with new value"

I read the MCP version 3.5 did NOT support write long. I really hoping version 3.6 does.

If 3.6 does support write long. How do I get my app to accept the long write. I have set the extend property.reliable_wr = 1. Is there anything else I need to do to handle this?

Thanks, Clint

[Bjørn Inge]

Support for long write was added in MCP 3.6.0, that is correct.

Update: To receive an incoming long write request correctly in your app you will need to handle the BLE_EVT_USER_MEM_REQUEST event (evt_id 0x02). The event needs to be responded to with sd_ble_user_mem_reply(conn_handle, p_block).

Next a BLE_GATTS_EVT_WRITE will be received, notifying that the value has been written.

Have a look at this thread: Writing long characteristic values.

[c cook]

Bjorn - I added BLE_GATTS_OP_EXEC_WRITE_REQ_NOW as a case in on_ble_evt(...). After clicking the Write Long button in MCP p_ble_evt->header.evt_id = 0x0012.

For reference - I'm using SDK 7.1, PCA10028 eval board, SD110 7.1, MCP 3.6.0.8331

[c cook]

UPDATE: I coded up the UART to dump all BLE event ids to a terminal. When I click the Write Long button in the MCP, it is consistently generating a p_ble_evt->header.evt_id = 0x0002. The 0x0012 event comes later, which I believe is a connection parameters update.

I’m not sure what BLE Event is 0x0002 – in the ble_gatts.h file all the BLE events are enumurations, and start with some base offset. I haven’t located any that start with base 0x0000. I added a case 0x0002: to on_ble_evt(ble_evt_t * p_ble_evt) and placed a break point at case 0x0002, so I could look at the data pointed to by p_ble_evt. No where do I see the data I’m trying to write. This makes be believe the stack needs me to respond, but because I don’t know what event 0x0002 is I can’t respond to the stack.

What BLE event is assigned to 0x0002 – and where or how do I find my data?

Also, if I do a Read Long after a Write Long, the data is unchanged (the write long did not write)

[Bjørn Inge]

Event id 0x0002 is BLE_EVT_USER_MEM_REQUEST and needs to be handled. See the updated post.