Connecnting to TE M5600 bluetooth 4.0 pressure sensor

Question

I am trying to connect TE connectivity M5600 wireless pressure sensor (http://www.te.com/usa-en/product-CAT-PTT0063.html) to Raspberry pi with no luck. The sensor is using Bluetooth 4.0. The sensor is working because I can connect it to my Android phone using TE connectivities app. Raspberry has latest Rasbpian with updates installed. Bluez version is 5.43. I have tried different tools to connect to the sensor, but nothing has worked so far. I have tried with bluetoothctl, hcitool and gattool. All of the tools can see the device when scanning. I also tried disabling the internal bluetooth controller and using usb bluetooth adapter, but everything was the same.

Here is some output from the tools I used: https://pastebin.com/62SLWBe2

Answer 1

I have the m5600 talking to the Raspi with the built-in Bluetooth.

This required a kernel modification to change the HCI_LE_CUTOCONN_TIMEOUT. This is originally set at 2 seconds. Changing to 20 seconds allows the connection to be made.

root@raspberrypi:/home/pi# hcitool lescan
LE Scan ...
14:99:E2:F5:37:06 (unknown)
EA:59:25:B9:71:EC TESS 5600
EA:59:25:B9:71:EC (unknown)
^C
root@raspberrypi:/home/pi# gatttool -b EA:59:25:B9:71:EC -t random -I
[EA:59:25:B9:71:EC][LE]> connect
Attempting to connect to EA:59:25:B9:71:EC
Connection successful
[EA:59:25:B9:71:EC][LE]> char-desc
handle: 0x0001, uuid: 00002800-0000-1000-8000-00805f9b34fb
handle: 0x0002, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x0003, uuid: 00002a00-0000-1000-8000-00805f9b34fb
handle: 0x0004, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x0005, uuid: 00002a01-0000-1000-8000-00805f9b34fb
handle: 0x0006, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x0007, uuid: 00002a04-0000-1000-8000-00805f9b34fb
handle: 0x0008, uuid: 00002800-0000-1000-8000-00805f9b34fb
handle: 0x0009, uuid: 00002800-0000-1000-8000-00805f9b34fb
handle: 0x000a, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x000b, uuid: 00002a29-0000-1000-8000-00805f9b34fb
handle: 0x000c, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x000d, uuid: 00002a24-0000-1000-8000-00805f9b34fb
handle: 0x000d, uuid: 00002a24-0000-1000-8000-00805f9b34fb
handle: 0x000e, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x000f, uuid: 00002a27-0000-1000-8000-00805f9b34fb
handle: 0x0010, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x0011, uuid: 00002a26-0000-1000-8000-00805f9b34fb
handle: 0x0012, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x0013, uuid: 00002a28-0000-1000-8000-00805f9b34fb
handle: 0x0014, uuid: 00002800-0000-1000-8000-00805f9b34fb
handle: 0x0015, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x0016, uuid: f0002a19-0451-4000-b000-000000000000
handle: 0x0017, uuid: 00002901-0000-1000-8000-00805f9b34fb
handle: 0x0018, uuid: 00002902-0000-1000-8000-00805f9b34fb
handle: 0x0019, uuid: 00002800-0000-1000-8000-00805f9b34fb
handle: 0x001a, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x001b, uuid: f000ab31-0451-4000-b000-000000000000
handle: 0x001c, uuid: 00002901-0000-1000-8000-00805f9b34fb
handle: 0x001d, uuid: 00002902-0000-1000-8000-00805f9b34fb
handle: 0x001e, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x001f, uuid: f000ab32-0451-4000-b000-000000000000
handle: 0x0020, uuid: 00002901-0000-1000-8000-00805f9b34fb
handle: 0x0021, uuid: 00002902-0000-1000-8000-00805f9b34fb
handle: 0x0022, uuid: 00002803-0000-1000-8000-00805f9b34fb
handle: 0x0023, uuid: f000ab3f-0451-4000-b000-000000000000
handle: 0x0024, uuid: 00002901-0000-1000-8000-00805f9b34fb
[EA:59:25:B9:71:EC][LE]> char-read-hnd 0x001b
Characteristic value/descriptor: b5 0b b5 89 35 00 00 00 00 00 44 9d 3b 01
[EA:59:25:B9:71:EC][LE]> char-read-hnd 0x001b
Characteristic value/descriptor: b5 0b 8b 85 35 00 00 00 00 00 44 9d 3b 01
[EA:59:25:B9:71:EC][LE]> char-read-hnd 0x001b
Characteristic value/descriptor: b5 0b 1b 86 35 00 00 00 00 00 44 9d 3b 01
[EA:59:25:B9:71:EC][LE]> char-read-hnd 0x001b
Characteristic value/descriptor: b5 0b 82 8a 35 00 00 00 00 00 44 9d 3b 01
[EA:59:25:B9:71:EC][LE]> char-read-hnd 0x001b
Characteristic value/descriptor: b5 0b 27 86 35 00 00 00 00 00 44 9d 3b 01

I'm currently running stretch with Bluez 5.49.

I cross compiled the kernel on my Fedora server from instructions at: https://akanto.wordpress.com/2012/09/25/cross-compiling-kernel-for-raspberry-pi-on-fedora-17-part-1/ and https://www.raspberrypi.org/documentation/linux/kernel/building.md

I grabbed the current raspi kernel config with:

modprobe configs
zcat /proc/config.gz > .config

Then, ran a make oldconfig to update it with the new options.

Prior to running make, update HCI_LE_CUTOCONN_TIMEOUT to 20 seconds in include/net/bluetooth/hci.h.

On a side note, I was previously able to use the Laird BT900 USB dongle in serial mode to access this device without a problem. You can connect serially and run gatttool to communicate with the m5600. But, I wanted it native to the raspi. The updated kernel solution will work much better for me.

I’d be interested to know what you’re doing with this device.