ADV modification for multi-hello sensors with 1 hello-client.

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Anonymous
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We come out a question there, if we put many hello-sensors in one big interior area
but "Don't connect" any with 1 client master which only receives slave devices' broadcast data
and firmware put all sensor data in broadcast field and send it via broadcast channel.

If so, in 20-byte length format, we can all replace all bytes to replace with our sensor data?
Is BT client can get correct ADV or it doesn't work.

to sum up with this mechanism,

- all sensors (slave devices) put sensor data in ADV and send it out; client master can get

many ADV of different area sensor data.

- if so, client can still call other API to get MAC addr or coz broadcast format is wrong,
even free APP of handset can not scan it correctly?

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Anonymous
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Hello again.

Here is an apk for a simple Scanner app.

It should work with most of Android devices.

With this app, you should be able to see the data of the advertisement packets.

Let us know if this helped or if you need any other questions.

Thank you.

ps. I think the app is pretty simple to use, so I didn't write any directions as to how to use the app.

     If anything is confusing, let me know.

James

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6 Replies
Anonymous
Not applicable

Hello.

To reiterate your situation, you want to use multiple hello_sensors as just broadcasters that broadcast advertisements and you want one hello_client to pick up on those advertisement packets, right?

This is possible, but you need to assign different BD_ADDRESSes to all the hello_sensors.

You can do this by changing the target name in the SDK to have different BD_ADDRESSes.

ex. "hello_sensor-BCM920736TAG_Q32 download BT_DEVICE_ADDRESS=20737A987654"

Please refer to Advertiser and Scanner for manipulating advertisement packets and how to scan them.

Please let us know if this helps. Thank you.

James

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Anonymous
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Hi, James,

thx and  another question,

I know broadcast payload length is 20B in BLE format.
if we broadcast with MAC (it includes 6Bytes) and once the hello sensor values
size is over 14Bytes, how to include all in one packet send or we need to segmentation?

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Anonymous
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You don't have to include MAC in your broadcast payload.

You can put whatever information you want in the payload and the advertisement would still have the name, address(MAC), and RSSI.

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Anonymous
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jamesle1

Can u suggest Android APP to analyze ADV(broadcasting data) to analyze hello-sensor broadcast coz
current free APP only shows MAC and need to make connection to get other service data.

Thx.

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Anonymous
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Currently I don't know any Android apps with the ability to see the advertisement packets. If you have a BLE dongle, you can sniff the packets from your computer. I'll try working on a simple Android app and post the apk here till Friday. Thanks.

0 Likes
lock attach
Attachments are accessible only for community members.
Anonymous
Not applicable

Hello again.

Here is an apk for a simple Scanner app.

It should work with most of Android devices.

With this app, you should be able to see the data of the advertisement packets.

Let us know if this helped or if you need any other questions.

Thank you.

ps. I think the app is pretty simple to use, so I didn't write any directions as to how to use the app.

     If anything is confusing, let me know.

James