JDY-08 Bluetooth LE Module - Datasheet, Fritzing part

Projects Networking, Protocols, and Devices
21

Now it is, my laptop BLE card had an issue. I've connected and discovered several characteristics. At this point my knowledge falls short.

I assume given there's no official protocol that if I'm in "transparent" mode (is that still AT+HOSTEN3?) then writing a character will change one of these characteristics and another characteristic will act as a flag which the master will poll and then know when to pull a value. Is that right?

If so what's the best way of going about working it out, writing a char to UART and checking each one?

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22

I just used the HM-10 service and char UUID's:

service UUID: 0000ffe0-0000-1000-8000-00805f9b34fb
RX characteristic UUID: 0000ffe1-0000-1000-8000-00805f9b34fb
TX characteristic UUID: 0000ffe1-0000-1000-8000-00805f9b34fb

23

So the characteristic is set to NULL to indicate it's been read? How large is the RX/TX characteristic?

24

I honestly don't know, I used an app to communicate.

25

Are you sure you used 0000ffe0-0000-1000-8000-00805f9b34fb?

I have this service but it has no characteristics.

I also have two others for Generic Access and Generic Attribute but as the name implies I believe these are Generic (one contains the device name for example).

Maybe 0000ffe0-0000-1000-8000-00805f9b34fb is correct but the characteristics are not exposed until the device is switched into pass-through...?

Andrew

26

Yup I used "0000ffe0-0000-1000-8000-00805f9b34fb" for the service UUID and "0000ffe1-0000-1000-8000-00805f9b34fb" for both RX and TX characteristic UUID. I used "AT+HOSTEN0"

27

I've got JDY-10 wired up and commands are working. There are three services;

attr handle: 0x0001, end grp handle: 0x0007 uuid: 00001800-0000-1000-8000-00805f9b34fb
attr handle: 0x0008, end grp handle: 0x0010 uuid: 0000ffe0-0000-1000-8000-00805f9b34fb
attr handle: 0x0011, end grp handle: 0x001b uuid: 0000fee7-0000-1000-8000-00805f9b34fb

I read the characteristics from the second service which the manual says is the "transparent transmission service";

handle: 0x0009, char properties: 0x14, char value handle: 0x000a, uuid: 0000ffe1-0000-1000-8000-00805f9b34fb
handle: 0x000d, char properties: 0x14, char value handle: 0x000e, uuid: 0000ffe2-0000-1000-8000-00805f9b34fb

I assume these map to RX/TX. The manual says ffe1 is the "pass-through characterised ID"

Neither of this characteristics have any value.

Unlike JDY-08 there's no master/slave mode, so the question now is now to get data from UART in/out of these characteristics.

According to text regarding pin B0, the device enters transparent mode when a bluetooth connection is established, but can be overridden by this pin. Since I've left it floating I would expect the AT commands to cease operating upon connection, yet they don't.

Both these characteristics have a descriptor;

[A4:C1:38:77:28:E6][LE]> char-desc 0x0009 0x0009
handle: 0x0009, uuid: 00002803-0000-1000-8000-00805f9b34fb
[A4:C1:38:77:28:E6][LE]> char-desc 0x000d 0x000d
handle: 0x000d, uuid: 00002803-0000-1000-8000-00805f9b34fb
[A4:C1:38:77:28:E6][LE]> char-read-uuid 00002803-0000-1000-8000-00805f9b34fb
handle: 0x0002 	 value: 12 03 00 00 2a 
handle: 0x0004 	 value: 02 05 00 01 2a 
handle: 0x0006 	 value: 02 07 00 04 2a

Which I figure with the char-properties bitmask value 0x14 sets read/write/notification etc. Unsure at this point though.

If I attempt a write;

[A4:C1:38:77:28:E6][LE]> char-write-cmd 0x000e 0x01
[A4:C1:38:77:28:E6][LE]> char-read-hnd 0x000e
Characteristic value/descriptor:
[A4:C1:38:77:28:E6][LE]> char-write-cmd 0x000a 0x01
[A4:C1:38:77:28:E6][LE]> char-read-hnd 0x000a
Characteristic value/descriptor:

No value for either, nothing in UART.

Unsure where to head next.

28

Some progress, I found a Chinese app for the JDY-08 and the two UUID's of interest are;

00002902-0000-1000-8000-00805f9b34fb (notificiation)
0000ffe1-0000-1000-8000-00805f9b34fb (tx/rx - looks like half duplex?)

Setting notifications to "1" puts the device into transparent mode

[A4:C1:38:77:28:E6][LE]> char-read-uuid 00002902-0000-1000-8000-00805f9b34fb
handle: 0x000b 	 value: 00 00 
[A4:C1:38:77:28:E6][LE]> char-write-cmd 0x000b 01 00

Now UART text comes through;

Notification handle = 0x000a value: 41 54 2b 4e 41 4d 45 0d 0a 
Notification handle = 0x000a value: 41 54 2b 4e 41 4d 45 0d 0a 
Notification handle = 0x000a value: 41 54 2b 42 41 55 44 0d 0a 
Notification handle = 0x000a value: 31 30 0d 0a 
Notification handle = 0x000a value: 31 0d 0a

However checking 0000ffe1-0000-1000-8000-00805f9b34fb offers no value, so perhaps this is a FIFO buffer.

Anyhow, doing a write to this char pumps it through to UART;

[A4:C1:38:77:28:E6][LE]> char-write-req 0x000a 01105D3A
Characteristic value was written successfully

So mission complete. :slight_smile: Use the DISC pin to force a disconnect, or for a pre-configure prior to allowing a connection to go through.

29

see this video

I have completed the communication between two jdy-08-ble modules.
for further information connect me on youtube. I will help you.

30

See this video
JDY 08 BLE bluetooth v4 Master Slave with arduino - YouTube
Here you will see my project that I have completed the communication between two jdy-08-ble modules.
for any issue regarding to this module contact me on youtube via comment your problem in my video.
Verge2050.

31

arturx:
Is here anyone who can provide me simple instruction or share your code, that allows to communicate with JDY-8 from remote linux system with BLE dongle?

What I want to achieve is just to set "0" or "1" to power off/on LED.

Thanks.

If you stick with genuine HM-10 and the Huamao software that exposes i/o pins, you can use digital i/o, ADC, and PWM directly on the module without any AT pass-through nonsense to another MCU.

I show here..

HM-10 BLE Android App using HM10 & AI2 only. NO ARDUINO