Feature Overview

MSB (Most Significant Bit) and LSB (Least Significant Bit) define the order in which binary data is read from an access card. Understanding and configuring MSB & LSB correctly ensures compatibility with RF card readers.


Understanding MSB & LSB

What is MSB?

  • MSB (Most Significant Bit) means the binary data is read from left to right, starting with the highest value bit.

What is LSB?

  • LSB (Least Significant Bit) means the binary data is read from right to left, starting with the lowest value bit.

Example

For a card ID of 1559994371 (MIFARE Classic), its binary representation is:

  • Decimal: 1559994371
  • Binary: 01011100 11111011 10100000 00000011

If read using:

  • MSB: The data is interpreted in its original left-to-right order.
  • LSB: The data is read in reverse order.


Configuring MSB & LSB in Airfob Portal

Step 1: Access Credential Settings

  • Go to Settings > Credential Settings.

Step 2: Select MSB or LSB

  • Choose either CSN MSB or CSN LSB based on your RF card reader's configuration.

Note: Only Master Admins have access to the Credential Settings menu.