
RFID Communications
In Continuous Read mode, the LEDs indicate the following:
LED | Behavior | Description |
ANT | ON | Assumes the antenna is powered and functioning |
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CONFIG | BLINK | Tag entered the RF field |
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RF | ON | Tag has been read and is still in the field |
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RF | OFF | Read tag has been out of range for the specified time |
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The command and response from the controller are formatted as follows.
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Field | Remarks |
| MSB | LSB | Remarks |
Command | Command number in hex preceded by AAH |
| AAH | 0DH | Command Echo |
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Start Address | 2 byte value for the start address in the tag |
| FFH | FFH | Message Terminator |
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Read Length | 2 byte value for the read length |
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Delay Between | Time the tag must be out of the antenna range before |
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Identical Decodes | the controller will transmit data again from that tag. |
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| Value is expressed in 1 second units |
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Message Terminator | FFFFH |
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This example places the controller in Continuous Read mode and reads eight bytes of data from the tag starting at address 0001H. A delay between identical reads of 2 seconds (0002H =2 x 1 second increments) is set.
Command from Host
MSB | LSB | Remarks |
AAH | 0DH | Perform Command D |
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00H | 01H | Start address |
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00H | 08H | Read 8 bytes |
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00H | 02H | |
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FFH | FFH | Message Terminator |
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Response from controller
MSB | LSB | Remarks |
AAH | 0DH | Command Echo |
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00H | 52H | Read data byte 1 |
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00H | 46H | Read data byte 2 |
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00H | 49H | Read data byte 3 |
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00H | 44H | Read data byte 4 |
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00H | 41H | Read data byte 5 |
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00H | 20H | Read data byte 6 |
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00H | 54H | Read data byte 7 |
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00H | 61H | Read data byte 8 |
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FFH | FFH | Message Terminator |
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The controller first returns an acknowledgment of the command followed by a response containing read data when a tag enters the antenna field.
65 | LRP2000 Passive Reader/Writer |