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Viewing 15 posts - 1 through 15 (of 36 total)
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  • in reply to: Impinj Reader Compatibility #1540
    Greg Pitner
    Community Member
    • ★★★★

    Unfortunately, the R420 and R220 are not capable of reading temperature on the current generation of temperature tags. The root cause is that the Impinj firmware ignores software commands to send Select commands with zero-length masks (which is what’s required to activate the temperature measurement on the tag).

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    in reply to: Spec. of RFID TAG Chip #1532
    Greg Pitner
    Community Member
    • ★★★★

    Please contact sales@axzon.com for any documentation that is not available on the website.

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    in reply to: RFM3200 #1530
    Greg Pitner
    Community Member
    • ★★★★

    Please see the documentation for the 3200 on the website, and contact sales@axzon.com if you need additional information.

    Your transmit power strategy sounds good, but I suspect it will be pretty difficult to achieve that sample rate. You might also consider using Select commands to choose specific subsets of the tag population that all need the same power level. That way you are only trying to talk to tags that have optimized power levels.

    There’s not really a precise mapping between On-Chip RSSI and power levels in dBm. If a tag reports an On-Chip RSSI of 1, then it just barely has enough power to operate. If it reports a value of 31, it is receiving very roughly 15 dBm more power than needed to turn on.

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    in reply to: RFM3200 #1526
    Greg Pitner
    Community Member
    • ★★★★

    Hi Steve,

    I may not be able to fully answer your questions in this format. I’ll make an attempt, but please feel free to contact us at sales@axzon.com for anything I don’t cover below.

    First, just to make sure we’re on the same page, the Sensor Code (which essentially reports the outcome of the auto-tuning process) is distinct and independent of the Temperature Code.

    To target a specific tag, you can use a Select command which specifies a particular EPC. Your reader will have to be capable of sending at least 2 Select commands in each inventory (communication cycle), since you will also need one to activate the temperature calculation on the tag(s). The specific details on how to do this will depend on the reader you’re using.

    The Sensor Code is a 9-bit value, so it theoretically varies from 0 to 511. In practice, due to some subtleties in how it works, the values will not generally swing quite that far — usually they will range from around 5 to around 490. The auto-tuning process happens as soon as the tag wakes up and before any formal communication is established with the reader, so it doesn’t impact temperature reading in any way.

    This process can’t be adjusted or deactivated. We do make a temperature-sensing chip that does not have auto-tuning, but it is currently only available on a different kind of tag: the RFM3240. If you can share what you trying to achieve by making the auto-tuning work differently, then we might be able to offer some advice.

    Greg

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    in reply to: Technical Spec. of RFM3xxx Temp sensors #1515
    Greg Pitner
    Community Member
    • ★★★★

    The 3250 sensor is essentially a small ceramic block with the sensor chip (where the temperature is measured) connected to the exterior of the block. The response time depends on several factors, such as the nature of the heat source and airflow effects. Speaking very generally, the T90 time is roughly several seconds.

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    in reply to: Monitor Wireless Sensor Remotely via Smartphones #1499
    Greg Pitner
    Community Member
    • ★★★★

    Hi Randy, fixed RFID readers connect to computers, and then from there it’s up to the software to process the data in any desired way, including sending it to a cloud. So any fixed reader which readers our sensors could potentially work — it’s more of a software than hardware question.

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    in reply to: Monitor Wireless Sensor Remotely via Smartphones #1497
    Greg Pitner
    Community Member
    • ★★★★

    Hi Randy, our sensors can be read with several kinds of UHF RFID readers. You can contact sales@rfmicron.com if you are interested in purchasing one.

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    in reply to: Software kit for reading moisture sensor tags #1495
    Greg Pitner
    Community Member
    • ★★★★

    There is a demo application included with that kit, but it doesn’t come with the source code itself. If you have a specific question, you can contact the sales team directly at sales@rfmicron.com.

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    in reply to: Software kit for reading moisture sensor tags #1493
    Greg Pitner
    Community Member
    • ★★★★

    Thanks for your question. We don’t give out the source code to our software products, but there is a lot of sample C# code in Application Note AN002, if you haven’t checked that out already.

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    in reply to: I can't read a specific TID sensor. #1491
    Greg Pitner
    Community Member
    • ★★★★

    It’s not possible to send multiple Select commands in the same inventory round using ThingMagic readers right now. That could change in the future, though. Their documentation mentions future support for a Multifilter object.

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    in reply to: RFM3200 Wireless Flexible Temperature Sensor #1485
    Greg Pitner
    Community Member
    • ★★★★

    The 3250 sensor is smaller, but is a ceramic tag intended to be applied to a metal surface, so it may or may not be what you are looking for. If you’d like to look into alternatives, please send an email to sales@rfmicron.com.

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    in reply to: I can't read a specific TID sensor. #1481
    Greg Pitner
    Community Member
    • ★★★★

    Hi,

    Just as you use a Select command to activate the temperature calculation on the sensor, you can also use a Select command to choose a particular EPC and tell any others to ignore subsequent commands. The details involve the way the UHF RFID tags work, and the specifics of the reader you are using. Keep in mind that you should send both the temperature Select and the EPC Select at the beginning of the same inventory round.

    1+
    in reply to: sensor response time #1479
    Greg Pitner
    Community Member
    • ★★★★

    Hi Khalid,

    The RFM3200 measures the temperature of the chip on the tag. The chip has a small thermal mass, and it generally heats or cools to the ambient temperature within seconds.

    In terms of the time required to read the tag, this can depend on a lot of things, like the RFID reader used, the reader settings, the number of tags in the area, the distance between the reader and tags, and other factors. Generally speaking though, you can get a single temperature reading from a tag around 2-10 times per second.

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    in reply to: Reading Temperature with Nordic ID AR52 #1432
    Greg Pitner
    Community Member
    • ★★★★

    Hi Sebastián, thanks for your interest. The Hermes code is for a separate development system, not for a 3rd party reader. One of your options is to write your own program to read temperature. Our Application Note AN002 contains sample Nordic ID C# code to get you started. It is available for download on the website.

    Also, we are starting to provide a Java-based programming API (the RfmApi) which supports the AR52, so this is another option. It is mentioned at the link below:

    Industrial IoT Sensor Platform

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    in reply to: Reading Temperature with Nur API –> Nordic UHF readers #1425
    Greg Pitner
    Community Member
    • ★★★★

    Hello,

    Below is C# code to read temperature using the Nur API, assuming the reader is a handheld model. Java is probably fairly similar, although I don’t have much experience with it. If you need more specific help, I recommend contacting tech support directly.

    Greg

    =================

    using System;
    using System.Linq;
    using System.Collections.Generic;
    using System.Text;
    using NurApiDotNet;
    using NordicId;
    namespace SimpleNordic
    {
    class Program
    {
    static void Main(string[] args)
    {
    NurApi hApi = new NurApi();
    hApi.ConnectIntegratedReader(); // Connect to internal reader module
    hApi.Region = NurApi.REGIONID_FCC; // Set frequency band to FCC (North American region)
    hApi.TxLevel = 5; // Set power level; 0=max, 19=min
    // Build a Select command using the CustomExchange method to activate the Magnus-3 temperature engine.
    // This approach makes it possible to insert a pause in between the transmission of the Select commmand
    // and the rest of the inventory round — increasing the accuracy of the temperature measurement.
    NurApi.CustomExchangeParams TempSelect = new NurApi.CustomExchangeParams();
    TempSelect.bitBuffer = new byte[NurApi.MAX_BITSTR_BITS / 8];
    int txLen = 0;
    txLen = NurApi.BitBufferAddValue(TempSelect.bitBuffer, 0xA, 4, txLen); // Command, Select (1010)
    txLen = NurApi.BitBufferAddValue(TempSelect.bitBuffer, 0x0, 3, txLen); // Target, S0 (000)
    txLen = NurApi.BitBufferAddValue(TempSelect.bitBuffer, 0x1, 3, txLen); // Action, matching assert SL (001)
    txLen = NurApi.BitBufferAddValue(TempSelect.bitBuffer, 0x3, 2, txLen); // MemBank, User (11)
    txLen = NurApi.BitBufferAddEBV32(TempSelect.bitBuffer, 0xE0, txLen); // Pointer, 0xE0
    txLen = NurApi.BitBufferAddValue(TempSelect.bitBuffer, 0x0, 8, txLen); // Length, 0 bits
    txLen = NurApi.BitBufferAddValue(TempSelect.bitBuffer, 0x0, 1, txLen); // Truncate, disable
    TempSelect.txLen = (ushort)txLen;
    TempSelect.asWrite = 1; TempSelect.txOnly = 1; TempSelect.noTxCRC = 0;
    TempSelect.rxLen = 0; TempSelect.rxTimeout = 20; TempSelect.appendHandle = 0;
    TempSelect.xorRN16 = 0; TempSelect.noRxCRC = 0; TempSelect.rxLenUnknown = 0;
    TempSelect.txCRC5 = 0; TempSelect.rxStripHandle = 0;

    NurApi.InventoryExParams InventoryParams = new NurApi.InventoryExParams();
    InventoryParams.inventorySelState = 0; // These definitions set RFID inventory parameters
    InventoryParams.inventoryTarget = 0;
    InventoryParams.Q = 0;
    InventoryParams.rounds = 5;
    InventoryParams.session = NurApi.SESSION_S0;
    NurApi.TagStorage tagStorage = new NurApi.TagStorage();
    hApi.InventoryRead(true, NurApi.NUR_IR_EPCDATA, NurApi.BANK_PASSWD, 0xE, 1); // Give location of temp code
    for (int cycle = 1; cycle <= 20; cycle++)
    {
    try
    {
    hApi.Inventory(1, 1, 0); // Run a pre-inventory to force a frequency hop
    hApi.ClearTagsEx();
    hApi.SetExtendedCarrier(true); // Turn on continuous wave (CW)
    hApi.CustomExchange(0, false, TempSelect); // Transmit Select command
    System.Threading.Thread.Sleep(3); // Pause for 3 ms while sending CW
    Console.WriteLine(“Read attempt ” + cycle);
    hApi.InventoryEx(ref InventoryParams, new NurApi.InventoryExFilter[0]); // Read tags
    tagStorage = hApi.FetchTags(true); // Get read results from buffer
    for (int i = 0; i < tagStorage.Count; i++)
    {
    Console.WriteLine(“EPC: ” + tagStorage[i].GetEpcString().ToUpper());
    int temperatureCode = (int)tagStorage[i].irData[0] * 256 + (int)tagStorage[i].irData[1];
    if (temperatureCode > 1000 && temperatureCode < 3500) // Use plausible values only
    Console.WriteLine(” Temperature Code: ” + temperatureCode);
    }
    }
    catch { }
    hApi.SetExtendedCarrier(false);
    hApi.ClearTagsEx(); // Clear contents of tag result buffer
    }
    hApi.Disconnect();
    Console.ReadLine();
    }
    }
    }

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Viewing 15 posts - 1 through 15 (of 36 total)