RFID Communications
6.4.11 ABxS Command 83H: Start/Stop Continuous SN Read All
DESCRIPTION
Command 83H starts and stops continuous read all mode for multiple tags. It reads the serial number and tag data. If the read length is zero (0), then only the tag's serial number is read. While in this mode, any other command can be issued and will be handled properly. After processing the new command, the controller resumes the continuous read. Continuous SN Read All is started or stopped by the start/stop byte in the command. A one (1) in the Start/Stop byte starts the continuous read and a zero (0) stops continuous read. The command has a parameter, Repeat Count, that can prevent multiple reads of the same tag. A tag is not read a second time until this specified number of tags have been read since it was last read. Allowed values are from 0 to 255, where 0 means the tag can be
Field | Remarks |
Command | Command number in hex preceded by AAH |
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Family ID | Tag Family ID - 00H = all tags |
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Reserved | 00H |
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Start Address | Tag address for the start of the read |
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Read Length | One word for the number of bytes to be read. |
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Repeat Count | Number of tag that must be read before the same tag will be read again |
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Start/Stop | 0001H to start, 0000H to stop |
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Message Terminator | FFFFH |
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Example
This example starts a continuous read of three bytes starting at address two, has a repeat count of four, and a family code of zero.
Command from Host
MSB | LSB | Remarks |
AAH | 83H | Perform Command 83 |
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00H | 00H | Tag Family 00/Reserved Byte |
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00H | 02H | Start Address |
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00H | 03H | Read Length of the data bytes |
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00H | 04H | Repeat count |
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00H | 01H | Stop/Start continuous read. This is to Start |
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FFH | FFH | Message Terminator |
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Response from Controller
MSB | LSB | Remarks |
AAH | 83H | Command Echo |
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FFH | FFH | Message Terminator |
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After the controller sends the acknowledgement, it sends the data read from the tags in the field.
MSB | LSB | Remarks |
AAH | 83H | Command Echo |
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00H | 1EH | Serial Number byte /Tag 1 |
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00H | 94H | Serial Number byte /Tag 1 |
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00H | 0BH | Serial Number byte /Tag 1 |
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00H | 01H | Serial Number byte /Tag 1 |
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LRP2000 Passive Reader/Writer | 70 |
