Exact role of Bluez in creating a virtual beacon - ibeacon

I use this code to transmit ibeacon profile over BLE.
sudo hciconfig hci0 up
sudo hcitool -i hci0 cmd 0x08 0x0008 1e 02 01 1a 1a ff 4c 00 02 15 e2 c5 6d b5 df fb 48 d2 b0 60 d0 f5 a7 10 96 e0 00 00 00 00 c5 00 00 00 00 00 00 00 00 00 00 00 00 00
sudo hcitool -i hci0 cmd 0x08 0x0006 A0 00 A0 00 03 00 00 00 00 00 00 00 00 07 00
sudo hcitool -i hci0 cmd 0x08 0x000a 01
hciconfig and hcitool are part of linux or these are Bluez commands? I used Bluez to create a beacon in a Raspberry Pi and I want to understand what is the exact role of Bluez in all this.

Yes, hciconfig and hcictrl are BlueZ command line tools. Systems without BlueZ installed will not have these commands.

Related

Lattice ECP5 UART, no signal on terminal emulator

I followed this tutorial to the letter, but I'll to explain in detail what steps I took exactly. I have an ECP5-evaluation 85k board.
I soldered bridges on R34/R35 (RX/TX) and R21 (connects LED D1 to RXD)
I used my windows installation to run the latest version of FT_PROG. In FT_PROG I went to FT_EEPROM -> Hardware Specific -> Port B -> Hardware and set it to RS232 and hit program. It completed succesfully according to the software.
Then I forwarded the USB port to my virtual box linux machine. It recognizes the board and I can succesfully run verilog files on it.
I ran ./raw_serial.sh to upload raw_serial.v to my board which is supposed to repeatedly print A to the serial monitor.
I then opened minicom on /dev/ttyUSB1 and it recognizes the device, baudrate is set correctly.
I then tried to use cu as follows: sudo chmod 666 /dev/ttyUSB1 && sudo cu -l /dev/ttyUSB2 -s 115200. It opens a terminal and says it is connected.
Led D1 is lighting up and both terminal programs indicate that the connection is succesful (I tried one of them at a time of course). Nothing is printed to the screen. When I use minicom and reupload raw_serial.v some <?> signs are printed to the screen but that's it. I tried turning echo on and off but nothing seems to work.
The following worked for me and it will probably work for others too. I'm assuming you're using openocd.
Do not use FT_PROG in windows, it doesn't seem to actually flash the FTDI chip. However, it lets you read back the hex dump that was supposed to be flashed to the chip. The hex dump for the unchanged EEPROM as it comes out of the box is as follows:
00000000 01 08 03 04 10 60 00 07 C0 FA 08 00 11 11 9A 10 .....`..Àú....š.
00000010 AA 3C E6 12 00 00 00 00 56 00 00 00 00 00 00 00 ª<æ.....V.......
00000020 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000040 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000050 00 00 00 00 00 00 02 03 00 00 00 00 00 00 00 00 ................
00000060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000070 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000080 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000090 00 00 00 00 00 00 00 00 00 00 10 03 4C 00 61 00 ............L.a.
000000A0 74 00 74 00 69 00 63 00 65 00 3C 03 4C 00 61 00 t.t.i.c.e.<.L.a.
000000B0 74 00 74 00 69 00 63 00 65 00 20 00 45 00 43 00 t.t.i.c.e. .E.C.
000000C0 50 00 35 00 20 00 45 00 76 00 61 00 6C 00 75 00 P.5. .E.v.a.l.u.
000000D0 61 00 74 00 69 00 6F 00 6E 00 20 00 42 00 6F 00 a.t.i.o.n. .B.o.
000000E0 61 00 72 00 64 00 12 03 46 00 54 00 32 00 55 00 a.r.d...F.T.2.U.
000000F0 59 00 54 00 4A 00 56 00 00 00 00 00 00 00 FC 27 Y.T.J.V.......ü'
I just post this here for future reference, we're not going to use the stock eeprom.
We need to flash the eeprom to RS232-HS mode. To do so, we must first change the hex dump of the eeprom accordingly. To put channel B in RS232-HS mode we need to change the last column of the last row from ' to |. Create a hex file called eeprom_RS232.bin with the following contents:
00000000 01 08 03 04 10 60 00 07 C0 FA 08 00 11 11 9A 10 .....`..Àú....š.
00000010 AA 3C E6 12 00 00 00 00 56 00 00 00 00 00 00 00 ª<æ.....V.......
00000020 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000040 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000050 00 00 00 00 00 00 02 03 00 00 00 00 00 00 00 00 ................
00000060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000070 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000080 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000090 00 00 00 00 00 00 00 00 00 00 10 03 4C 00 61 00 ............L.a.
000000A0 74 00 74 00 69 00 63 00 65 00 3C 03 4C 00 61 00 t.t.i.c.e.<.L.a.
000000B0 74 00 74 00 69 00 63 00 65 00 20 00 45 00 43 00 t.t.i.c.e. .E.C.
000000C0 50 00 35 00 20 00 45 00 76 00 61 00 6C 00 75 00 P.5. .E.v.a.l.u.
000000D0 61 00 74 00 69 00 6F 00 6E 00 20 00 42 00 6F 00 a.t.i.o.n. .B.o.
000000E0 61 00 72 00 64 00 12 03 46 00 54 00 32 00 55 00 a.r.d...F.T.2.U.
000000F0 59 00 54 00 4A 00 56 00 00 00 00 00 00 00 FC 27 Y.T.J.V.......ü|
Now, we need to flash this eeprom to our ECP5 using Anton's method. To do this, first create a file ftdi_RS232.conf with the following contents:
vendor_id=0x403
product_id=0x6010
filename="eeprom_RS232.bin"
flash_raw=true
With the following command we can flash to our ECP5: ftdi_eeprom --flash-eeprom ftdi_RS232.conf. Should we ever want to revert back to the stock eeprom, we can easily repeat this method with the hex dump given in step 1.
Now it's time to flash the verilog file. However, the device description of the ECP5 has changed from Lattice ECP5 Evaluation Board to Dual RS232-HS. We need to tell openocd to look for that specific device. Start by creating a file ecp5.cfg with the following contents:
# this supports ECP5 Evaluation Board
interface ftdi
ftdi_device_desc "Dual RS232-HS"
ftdi_vid_pid 0x0403 0x6010
# channel 1 does not have any functionality
ftdi_channel 0
# just TCK TDI TDO TMS, no reset
ftdi_layout_init 0xfff8 0xfffb
reset_config none
# default speed
adapter_khz 5000
# ECP5 device - LFE5UM5G-85F
jtag newtap ecp5 tap -irlen 8 -expected-id 0x81113043
Then, create your svf file as you usually do and flash it with the following command:
sudo --preserve-env=PATH env openocd -f ./ecp5.cfg -c "transport select jtag; init; svf raw_serial.svf; exit"
Finally, we can open a terminal to read the serial output of the ECP5. Personally, I like to use minicom: sudo chmod 666 /dev/ttyUSB0 && minicom -D /dev/ttyUSB0.
One more problem with the raw_serial.v example was that it doesn't use a baudrate of 115200 as the readme suggests but 19200. The clock that is connected to the FTDI chip runs at 12 MHz. If you want a baudrate of 115200 you need to send a bit every 12,000,000 / 115,200 ~= 104 ticks. This means you need to change line 14 to if (counter == 104) begin.

Relation between transminnion power and detection distance

I found this code and used it to start the transmission as a beacon
sudo hciconfig hci0 up
sudo hcitool -i hci0 cmd 0x08 0x0008 1e 02 01 1a 1a ff 4c 00 02 15 e2 c5 6d b5 df fb 48 d2 b0 60 d0 f5 a7 10 96 e0 00 00 00 00 c5 00 00 00 00 00 00 00 00 00 00 00 00 00
sudo hcitool -i hci0 cmd 0x08 0x0006 A0 00 A0 00 03 00 00 00 00 00 00 00 00 07 00
sudo hcitool -i hci0 cmd 0x08 0x000a 0
If I right understood, the value c5 00 is the transmission power which affect the detection range is that right?
What did this value mean and what is the relation between power and range? For example for a power of 5(is it Tx?) the detection rate is ... ?

Change Beacon transmission rate to 5Hz

I use this code to start a ibacon with a 10hz transmission rate.
sudo hciconfig hci0 up
sudo hcitool -i hci0 cmd 0x08 0x0008 1e 02 01 1a 1a ff 4c 00 02 15 e2 c5 6d b5 df fb 48 d2 b0 60 d0 f5 a7 10 96 e0 00 00 00 00 c5 00 00 00 00 00 00 00 00 00 00 00 00 00
sudo hcitool -i hci0 cmd 0x08 0x0006 A0 00 A0 00 03 00 00 00 00 00 00 00 00 07 00
sudo hcitool -i hci0 cmd 0x08 0x000a 01
Are the min and max values little endian ? I want to be sure that this value that my command is right.
sudo hcitool -i hci0 cmd 0x08 0x0006 50 00 50 00 03 00 00 00 00 00 00 00 00 07 00
Will this command change the transmission rate to 5Hz? And is the optimal scan period for this rate is 400ms ?
The min and max values are little endian, yes. So in this command:
sudo hcitool -i hci0 cmd 0x08 0x0006 50 00 50 00 03 00 00 00 00 00 00 00 00 07 00
The first two bytes 50 00 sets the min interval to 0x0050 (80 decimal), which at a granularity of 0.625 ms converts to 80x0.625 = 50.0 ms. The second two bytes sets the max interval to 50.0 ms as well. To convert to Hz, you take the reciprocal of the interval 1/(0.050 secs) = 20 Hz.
You say you want 5 Hz, which would be one advertisement every 1/(5 Hz) = 0.2 secs = 200 ms. At a granularity of 0.625 ms, that is 200/0.625 = 320 = 0x0140. Expressed as little endian this is 0x40 0x01. So to advertise at 5 Hz, do:
sudo hcitool -i hci0 cmd 0x08 0x0006 40 01 40 01 03 00 00 00 00 00 00 00 00 07 00
Your bluetooth chip may or many not support this rate. You will have to try and see. If it doesn't support it, you probably will get no errors, it just will advertise at its closest supported rate.
If you are scanning for this advertisement using the Android Beacon Library or some other library that lets you configure the scan interval, a default scan interval of ~1.0 sec will work fine.

Golang doesn't send UDP packet to multicast group

currently I try to reimplement a C application in go. Part of the C application is to send a string to a multicast group. This produces the following packet captured via tcpdump:
00000000 d4 c3 b2 a1 02 00 04 00 00 00 00 00 00 00 00 00 |................|
00000010 ff ff 00 00 01 00 00 00 14 81 06 56 47 2c 01 00 |...........VG,..|
00000020 46 00 00 00 46 00 00 00 33 33 00 02 10 01 04 ce |F...F...33......|
00000030 ef ca fe 1a 86 dd 60 00 00 00 00 10 11 01 fe 80 |......`.........|
00000040 00 00 00 00 00 00 06 ce ef ff fe ca fe 1a ff 02 |................|
00000050 00 00 00 00 00 00 00 00 00 00 00 02 10 01 be 8f |................|
00000060 03 e9 00 10 99 68 6e 6f 64 65 69 6e 66 6f |.....hnodeinfo|
I tried to replicate the behavior with the following code:
const MultiCastGroup string = "ff02:0:0:0:0:0:2:1001"
const Port int = 1001
const Proto string = "udp6"
const MaxDataGramSize int = 8192
var announcedAddr = &net.UDPAddr{IP: net.ParseIP(MultiCastGroup), Port: Port}
buf := []byte("nodeinfo")
unicastConn, _ := net.ListenUDP(Proto, &net.UDPAddr{IP: net.IPv6zero, Port: 0})
unicastConn.WriteToUDP(buf, announcedAddr)
But the I don't think that it is working, because all I can capture from this via tcpdump is:
00000000 d4 c3 b2 a1 02 00 04 00 00 00 00 00 00 00 00 00 |................|
00000010 ff ff 00 00 01 00 00 00 |........|
00000018
It doesn't seem that the packet is even send. I tried this on a Debian Wheezy machine. Did anyone if you encounter a similar problem with golang and UDP?
Thanks in advance
Did you try to listen for it on another host?
Go (at least in 1.4) had a hard coded disable of loopback on multicast. Which means that, you can't see your own packets.
You can override this by calling setsockopt on the socket FD itself, or:
The golang.org/x/net/ipv6 library can do this for you.
Or you can take the code from Here (have to poke around to find it)

Why do setpci and lspci -xxxx show different data for the same address?

On my x86 Linux system reading from different locations in PCI configuration space using setpci seems to give completely different answers for some registers when compared to output from lspci -xxxx.
For example, I pick an arbitrary device on my bus and do lspci -s 00:1f.3 -xxxx and get:
00: 86 80 22 1e 03 00 80 02 04 00 05 0c 00 00 00 00
10: 04 40 51 d0 00 00 00 00 00 00 00 00 00 00 00 00
20: a1 ef 00 00 00 00 00 00 00 00 00 00 28 10 8b 05
...
e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
f0: 00 00 00 00 00 00 00 00 87 0f 04 08 00 00 00 00
Now, the output from setpci -s 00:1f.3 0x40+0.l is 02800003 which is consistent with the output above. However, the output from setpci -s 00:1f.3 0xf8+0.l is ffffffff which from the dump above I would have expected to be 08040f87.
Can someone please help shed some light on what is going on here. I'm new to the world of PCI debugging, so I may be missing something obvious here.
Thanks in advance.
man setpci
setpci is a utility for querying and configuring PCI devices.
Root privileges are necessary for almost all operations, excluding reads of the standard header of the configuration space on some operating systems. Please see lspci(8) for details on access rights.
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