I made an app that discovers Bluetooth devices around me, and I'm looking into the datas I get about them. Now I'm trying to figure out the datas from BluetoothDevice.getBluetoothClass (CoD, Class of Device).
So far I've found these class codes around me:
43c
50c
704
1f00
c043c
c243c
8043c
60680
200408
240414
5a020c
About half of these I found some information for (http://domoticx.com/bluetooth-class-of-device-lijst-cod/). The rest of the codes I haven't been able to find anywhere (50c, c043c, c243c, 60680).
Does anyone know any overview with all of these codes (or at least the ones I haven't figured out)?
You can decode the Bluetooth Class of Device (CoD) yourself by first converting the above hex number to binary (for example using this link) and then checking the document below to try and find what the combination of the bits mean:-
https://www.ampedrftech.com/datasheets/cod_definition.pdf
As an example, 0x50c is 010100001100 in binary. Using the table in the document above, bits 8 to 12 indicate that the device is a peripheral:
And then bits 2 to 5 indicate that the device is a remote control
Related
I'm making a project with Esp32 whroom, so I bought the yj-16009 iBeacon DataSheet and I'm trying to get it to work as wireless Bluetooth proximity sensor like in this Video
I used the this code from the video and the esp32 is monitoring and showing BLT scanning results like this the results shown are after I turned off any BLT device around so first I don't understand what it is reading, and second after I turn on the iBeacon the results remain with the same range of numbers no matter if I get the iBeacon closer or farther, therefor I came to the conclusion that it doesn't recognize the iBeacon sensor for some reason.
I also download an app named LightBlue which does recognize the iBeacon sensor.
My question is if anyone knows how to make the esp32 recognize the iBeacon sensor. Another thing I tried to find any information about this sensor and there is no info about it anywhere. I have read on other questions here that it might need to be programmed somehow which I don't know how to do because there is no info online. So if anyone is familiar with this kind of sensor and can help me figure how to make the ibeacon to work like the video above as a Bluetooth Proximity device it would be a blessing.
The code you reference is just scanning for any BLE advertisements (iBeacon or otherwise) and printing out the RSSI signal strength of each detection. The reason you do not see the RSSI change when you move the beacon is because the ESP32 is probably picking up non-iBeacon adverts from your phone, laptop and other Bluetooth enabled devices in the vicinity which are not moving (there are more around you than you think!)
In order to make the device detect iBeacon only (and not all the other devices) you need to change the C code to do a few more things:
Access the bytes of the advertisement payload and use them as follows:
Compare the beginning of these bytes to see if they include the iBeacon byte sequence FF 4C 00 02 15
If the above byte sequence is not in the advertising data, ignore that detection — it is not an iBeacon advert
If it does include that byte sequence, decode the next 16 bytes as the iBeacon uuid, the next two bytes as the major and the next two bytes as the minor. See my answer here: What is the iBeacon Bluetooth Profile
Print out the identifiers along with the RSSI that the code already prints.
I'm sorting out how to achieve the following, I want to use smart or memory cards in a project. The cards should be read by standardized card readers (for example ACR38). When they are read by the computer ( command line or by a software (processing or p5js or similar), there should be a popup a window which shows the contents of the card being a picture and a text. Bit similar when I use my regular ID to be read by my E-idsoftware.
For the moment the card I have is this one SLE4428 (at the bottom instructions from the vendor)
These have no data on it yet and are bought blank
=> datasheet
The software I found but don't know if it's suited for my project and how to specifically use it is the following.
Opensource tools that I found when searching for SC cards software (no id how to use them.)
https://linux.die.net/man/1/opensc-tool
https://linux.die.net/man/1/opensc-explorer
I looked at my smartcard reader and found that http://www.acr38u.com/
is a platform but has to be payed for and I'm unable to found sofware for this on linux or apple.
Again here I found a datasheet with hex code to connect to the card, but still not how to physically connect to the cards.
This site shows many points of a working shell but I can't find the installer for it. opendsc
Then lastly this is the most promising and I already contacted the maker of it. But installation gets stuck in the make process (which I've already searched for and is not solution yet, being at it for a week now so therefore this post, maybe the community can help with an alternative look)
This is the explanation from the vendor side (Aliexpress) which is kind of specific. Though I don't know where to input these hex codes to write or read from the card. (there is a software but it's windows (If there is somebody that can say, that the way to solve the core question of my project then I'll try to get a windows pc to work on it via that way))
ISO7816 SLE 4442 Chip PVC Contact Smart Card (0.8* 85.5 * 54mm)
If you need write the 4442 cards,you should buy the contact smart reader writer!! 4442 cards not support 13.56mhz rfid writer!!!
NOTE:There is NO magnetic strip behind the card.
Graphics Quality Cards For All Photo ID Card Printers Including
DataCard, Zebra, Fargo, Evolis, Magicard, NBS & etc.
(These Cards Will Not Work In Inkjet Printers)
If you need 100pcs 4442 cards,pls check the links below:
[https://www.aliexpress.com/store/product/100-pcs-lot-ISO7816-RFID-Contact-SLE-4442-Chip-PVC-Smart-Card/516120_32425491077.html?spm=2114.12010608.0.0.R0bzFx][1]
Features:
Standard:ISO7816
Product Chip:SLE4442
Color:White
Dimension: L 85.5 x W 54 x H 0.80±0.04mm
256 × 8-bit EEPROM organization
32 × 1-bit organization of protection memory
erase cycles more than 100,000 times
Data retention for minimum of ten years
Default passwords: FFFFFF
3 bytes for error counter and card secret code area
1,Write protected area (first 32 bytes) of each byte can be individually write protected, After write,the data can't be changed.
2, Before checking the password, all the data can be read, if necessary,you could encryption data.
3, After confirm password is correct,the data could be write or modify.
4, The 3 bytes of user passwords, after confirm is correct,it could be change.
5, The password error counter, the initial value of 3, check the error code 1, then subtract 1, if the counter value is 0, the card is automatically locked, the data just read out, no longer change can no longer be password verification; if zero, the one time password verification is correct, restore to the initial value.
6, The byte address 0-5,6-7 factory prior written by the manufacturers can not be changed.
The specifics for this question lies in either
A: How can I achieve a working environment on linux or mac (first) to read and write data on an sc card (the one I have or !B: a working alternative)
C: Create a viewer program or webapp, etc.. to view or route the data to when the SC card is being read. (This would be a valid question, If i where to chose a Windows based existing program, I think)
Because this is not code specific, but I still want people that have the same questions to be able to see this page to show them pletora of scripts and ways to approach this or similar SC project.
This guy knows a lot about OpenSC!
I'm trying to set up my LabView VI + my USB 6001 I/O box to be able to read multiple independent voltages at once, while also outputting a single constant voltage.
I've successfully gotten my USB box to output the voltage I want while reading back a single voltage, but so far I've been unable to read back more than one voltage (and if I do, the two voltages seem to be co-dependent on one another in some way).
Here's a screenshot of my VI:
Everything to the right of the screenshot window should be unimportant to the question.
If anyone is curious, this is to drive multiple LVDT's and read back their respective voltages.
Thank you all for your help!
Look at your DAQ's manual, especially the pages I noted below.
http://www.ni.com/pdf/manuals/374259a.pdf
Page 11
All the AI channels get multiplexed, and the low-side reference can be switched (RSE vs. differential). So the two channels you're sampling require both of those to switch. It might be a settling issue where the ADC is taking a sample before the input value is stable.
To verify this, try using using the same low side (differential or RSE) on both channels. Also try slowing down your sample rate (but your 1 kHz should already be slow enough...).
Page 14
Check this to make sure you have everything connected and grounded correctly.
Page 18
Check this for more details about switching between 2 sources quickly.
Perhaps you could try it using the Daqmx express VIs:
http://www.ni.com/tutorial/2744/en/
I'm trying to write an application in pyserial to talk to an external device (a Casio graphics calculator) which according to its manual uses 9600bps asynchronous serial with no flow control, no parity and 8 bits, but for the stop bit values it specifies 3 stop bits for sending and 2 stop bits for receiving. The manual makes no mention of start bit length.
First, does anyone know how to specify two different stop bit values using pyserial, and secondly can you actually specify a stop bit length of 3? The only options that pyserial has are 1, 1.5 and 2 bits.
I've so far managed to send single characters from my Linux laptop to the graphics calculator (setting either 1 or 2 stop bits seemed to work) but getting characters back from the graphics calculator isn't working (I have tested both the cable and port and they should work), so I'm guessing the stop bit setting could be an issue. If anyone knows where to go from here, any help would be greatly appreciated!
Trying to get access to a partially rooted Galaxy S2 external sd card.
The problem is that /dev/block/mmcblk1p1 does not exist on the phone. This is the device name that should allow me to put the "recovery" image onto the sdcard so that the unit will be a phone again.
Problem is, I don't know where to find the magic Major and Minor numbers for this device and I'm trying to figure out where in the kernel source I should be looking for them.
Could someone point me at the right kernel files to find this information?
Standard devices use predefined major numbers and minor numbers starting from 0 for the first instance and upward depending on how many instances there are going to be.
Look at the Linux Documentation file(devices.txt) to see the full list but the section of interest to you is:
179 block MMC block devices
0 = /dev/mmcblk0 First SD/MMC card
1 = /dev/mmcblk0p1 First partition on first MMC card
8 = /dev/mmcblk1 Second SD/MMC card
...
The start of next SD/MMC card can be configured with
CONFIG_MMC_BLOCK_MINORS, or overridden at boot/modprobe
time using the mmcblk.perdev_minors option. That would
bump the offset between each card to be the configured
value instead of the default 8.
So /dev/block/mmcblk1p1 would be major 179, minor 9.
According to hotplug.txt
Entries for block devices are found at the following locations:
/sys/block/*/dev
/sys/block/*/*/dev
So try looking in /sys/block/mmcblk1p1/dev.
EDIT:
Looking at it again I actually think that it will be in /sys/block/mmcblk1/mmcblk1p1/dev