[S132, S140] char_props.write=0 doesn't prevent writing

RE: [S132, S140] char_props.write=0 doesn't prevent writing

Hung Bui — Wed, 01 Nov 2017 08:56:01 GMT

Sorry my mistake, yes NO_ACCESS will block :)

RE: [S132, S140] char_props.write=0 doesn't prevent writing

hgm-ble — Wed, 01 Nov 2017 08:47:08 GMT

BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.write_perm) will block any write to the characteristic.

Did you mean BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS? If so, it works! Thanks.

RE: [S132, S140] char_props.write=0 doesn't prevent writing

Hung Bui — Tue, 31 Oct 2017 14:39:26 GMT

Hi,

The char_props only set the properties of the characteristic. It doesn't prevent the characteristic being written. The properties are for information (to the peer) only.

If you want to prevent your characteristic being written, you need to use permission, for example attr_md.write_perm. Set BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.write_perm) will block any write to the characteristic.

To fix the length of the characteristic, you set vlen (Variable length attribute) = 0.