How to adjusting the RTC in VP5300 to make transaction times accurately reflect local time?

Owned by Yan Mu
Last updated: Jan 02, 2024
2 min read

A. To make the transaction time accurately reflect your local time, you can add or modify the value to the DFEF43 tag in your Group 0 settings.

  1. Download and install the .NET SDK Demo from Universal Library for Visual Studio - Home.

  2. Retrieve the reader's current date and time by sending the Get RTC Date and Time (25-06) command with no data (see below screenshot).  



  3. Please be aware that the date & time stored in the reader is the UTC.

  4. Define the 4-byte value of the DFEF43 tag based on the definition of the tag below:

    • Byte1: +/-, indicates the current timezone is ahead or behind UTC.

    • Byte2: HH, hours of the time difference between the local and UTC.

    • Byte3: MM, minutes of the time difference between the actual local time in the reader with UTC.

    • Byte4: Flag for daylight saving, set 1 to indicate daylight saving enabled.

    For example, if a device is located in California (PST), which is 7 hours behind the UTC and currently in Daylight Saving Time, and if the time retrieved from the reader is five minutes ahead of the actual local time, the four-byte value of DFEF43 should be 2D 07 05 01 where:

    • 2D is the hex code for the "-".

    • 07 is the hour that we are behind the UTC.

    • 05 is the minutes that the reader is currently ahead of the actual local time.

    • 01 indicates that the summer saving is on.


  5. Add Tag DF EF 43 04 2D 07 05 01 in Group 0 settings by sending the Set Configuration (04-00) command with data DF EF 43 04 2D 07 05 01 if Tag DFEF43 doesn't exist in your current group 0 or if you want to modify the value of the existing DFEF43 tag in Group 0.

  6. Finally, perform a transaction test to verify the transaction time (Tag 9F21) is reflecting the correct local time.  

If you need further help with this issue, send an email to our Support Portal (support@idtechproducts.com) with the following information provided so we can help you figure out the correct value for Tag DFEF43 in Group 0:

  1. The UTC date/time can be retrieved from your VP5300 by sending the Get RTC Date and Time (25-06) command with no data as shown in the screenshot above.

  2. The group 0 settings from your VP5300 reader by sending the Set Configuration (04-00) command with no data and sending us the response string. 

  3. Your location (State), the actual local time when the Get RTC Date and Time (25-06) command is sent, whether you are currently in the Daylight Saving Time.



Keep in mind though the UTC residing in the reader won't be affected by the value change of the DFEF43 tag.  Also, you may want to adjust it every once in a while if the time is drifting off over time.