“bletiny” is one of the sample applications that come with Mynewt. It is a simple shell application which provides a basic interface to the host-side of the BLE stack. “bletiny” includes all the possible roles (Central/Peripheral) and they may be run simultaneously. You can run bletiny on a board and issue commands that make it behave as a central or a peripheral with different peers.
Highlighted below are some of the ways you can use the API to establish connections and discover services and characteristics from peer devices. For descriptions of the full API, go to the next sections on GAP in bletiny and GATT in bletiny.
Currently the device public address is hardcoded to 0a:0b:0c:0d:0e:0f in bletiny app but you can change it by going into its source code and initializing it to the desired value as described in the section on how to initialize device addr.
In this case, your board is acting as a central and initiating a connection with another BLE device. The example assumes you know the address of the peer, either by scanning for available peers or because you have set up the peer yourself.
b conn addr_type=public addr=d4:f5:13:53:d2:43 [ts=118609ssb, mod=64 level=2] connection complete; status=0 handle=1 peer_addr_type=0 peer_addr=0x43:0xd2:0x53:0x13:0xf5:0xd4 conn_itvl=40 conn_latency=0 supervision_timeout=256
The handle=1 in the output indicates that it is connection-1.
In this case, your board is acting as a peripheral.
b set adv_data name=<your-device-name>
In this case, your board is acting as a peripheral.
b adv conn=und disc=gen
b show conn
This is how you discover and then display the services of the peer you established earlier across connection-1.
b disc svc conn=1 b show chr [ts=132425ssb, mod=64 level=2] CONNECTION: handle=1 addr=d4:f5:13:53:d2:43 [ts=132428ssb, mod=64 level=2] start=1 end=5 uuid=0x1800 [ts=132433ssb, mod=64 level=2] start=6 end=16 uuid=0x1808 [ts=132437ssb, mod=64 level=2] start=17 end=31 uuid=0x180a [ts=132441ssb, mod=64 level=2] start=32 end=65535 uuid=00000000-0000-1000-1000000000000000
The following examples show how to find the characteristics for each service available on the peer device across connection-1. The start and end values depend on the specific services discovered using the previous command b show chr. Continuing with the example above, you can discover the characteristics of the first service and display it using the following commands.
b disc chr conn=1 start=1 end=5 b show chr [ts=163063ssb, mod=64 level=2] CONNECTION: handle=1 addr=d4:f5:13:53:d2:43 [ts=163067ssb, mod=64 level=2] start=1 end=5 uuid=0x1800 [ts=163071ssb, mod=64 level=2] def_handle=2 val_handle=3 properties=0x02 uuid=0x2a00 [ts=163078ssb, mod=64 level=2] def_handle=4 val_handle=5 properties=0x02 uuid=0x2a01 [ts=163085ssb, mod=64 level=2] start=6 end=16 uuid=0x1808 [ts=163089ssb, mod=64 level=2] start=17 end=31 uuid=0x180a [ts=163094ssb, mod=64 level=2] start=32 end=65535 uuid=00000000-0000-1000-1000000000000000
You can next discover characteristics for the second service and display.
b disc chr conn=1 start=6 end=16 b show chr [ts=180631ssb, mod=64 level=2] CONNECTION: handle=1 addr=d4:f5:13:53:d2:43 [ts=180634ssb, mod=64 level=2] start=1 end=5 uuid=0x1800 [ts=180639ssb, mod=64 level=2] def_handle=2 val_handle=3 properties=0x02 uuid=0x2a00 [ts=180646ssb, mod=64 level=2] def_handle=4 val_handle=5 properties=0x02 uuid=0x2a01 [ts=180653ssb, mod=64 level=2] start=6 end=16 uuid=0x1808 [ts=180657ssb, mod=64 level=2] def_handle=7 val_handle=8 properties=0x10 uuid=0x2a18 [ts=180664ssb, mod=64 level=2] def_handle=10 val_handle=11 properties=0x02 uuid=0x2a51 [ts=180672ssb, mod=64 level=2] def_handle=12 val_handle=13 properties=0x28 uuid=0x2a52 [ts=180679ssb, mod=64 level=2] def_handle=15 val_handle=16 properties=0x02 uuid=0x2a08 [ts=180686ssb, mod=64 level=2] start=17 end=31 uuid=0x180a [ts=180691ssb, mod=64 level=2] start=32 end=65535 uuid=00000000-0000-1000-1000000000000000
Just as before, the start and end values depend on the specific characteristics discovered.
b disc dsc conn=1 start=1 end=5 b disc dsc conn=1 start=6 end=16 b disc dsc conn=1 start=17 end=31
b read conn=1 attr=18 attr=21
b write conn=1 attr=3 value=0x01:0x02:0x03
This is how you tell your board to listen to all advertisements around it. The duration is specified in ms.
b scan dur=1000 disc=gen type=passive filt=no_wl