Simultaneous RFID Tag Reader: Set read power error

Sensors NFC & RFID
1

Hi all,

I’m trying to use SRTR in max read TX power (27dBm). But it can read tags from 5dBm to 19dBm. If set higher, it can’t read any tags. That’s so weird. I’m using an external UHF antenna and a 5V external power adapter

Example2_Read_EPC

" nano.setReadPower(1900); //19.00 dBm. Higher values may cause USB port to brown out

//Max Read TX Power is 27.00 dBm and may cause temperature-limit throttling "

2

How are you cooling the shield? High power creates a lot of heat and if the module gets hot, it shuts down to protect itself.

  • - Can you send a clear, high resolution photo of the top and bottom of your shield and a photo showing how it’s connected up?

  • - Are you using our RFID antenna or a different one?
    • 3

    I used Universal Reader Assistant with USB to UART Bridge connected to USB 3.0 port and i can set SRTR in max read power without problem.

    Then I try it with arduino and i meet this problem. It doesn’t work, not to be shutted down by overheat.

    Is the library wrong?

    4

    Picture

    anh2.PNG
    anh2.PNG1950×915 56.9 KB

    anh1.PNG
    anh1.PNG1897×1004 69.7 KB

    5

    I enabled the logging on the URA and enabled debugging on the Arduino. The command for 27dB that is send is exactly the same and correct, also acknowledged by the Nano. : FF 02 92 0A 8C 4B D5. The one big difference with the URA is that with each change of the slider to the wanted power, it will send the command for the readpower that is current on the slider. E.g. if the starting point is 27db to 20 db, it will sent a change command for 26, 25, 24 23, 21 and 20bdb. I would not expect that to be reason. As you connect with USB to the PC, the VCC from the USB port is also providing power, unless you cut JP1 on the SRTR. A USB 3.0 can provide up to 900mA. Could that extra power make the difference ?