
AT88RF1354 SPI User Guide For CryptoRF
3.4.2
Example
String Decode > O0009 Host sends nine bytes thru microcontroller to AT88RF1354 serial port.
>
03
AT88RF1354 TX Data command.
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05
Data bytes sent to PICC. In this example 5 bytes are sent to the PICC.
>
01
PARAM. Bits[2:0] select AT88RF1354 Communication Protocol Register 1 (CPR1).
>
00
Timeout. A $00 selects the Frame Waiting Interval defined during CPR initialization.
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50
To PICC: HLTB Command.
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FF
To PICC: PUPI 0. Use the value from the PICC's Poll response.
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FF
To PICC: PUPI 1. Use the value from the PICC's Poll response.
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FF
To PICC: PUPI 2. Use the value from the PICC's Poll response.
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FF
To PICC: PUPI 3. Use the value from the PICC's Poll response.
The AT88RF1354 automatically appends RF communication CRC bytes to the transmitted data stream.
Wait for AT88RF1354 ISTAT pin state.
ISTAT goes High.
The AT88RF1354 buffer has data ready. Data must be read before the next command can be issued.
>
I0004 Host gets four bytes from AT88RF1354 buffer.
>
00
AT88RF1354 Response: $00 (No RF communication error bits set in the EREG register).
>
01
AT88RF1354 Response: PICC response byte count.
>
01
AT88RF1354 Response: PARAM. Echo PARAM byte used in prior TX Data command.
>
00
PICC Response: $00 is the success response. No PICC response is sent if the command contained errors.
The AT88RF1354 automatically strips the RF communication CRC bytes.
ISTAT stays Low.
The AT88RF1354 buffer is empty. The AT88RF1354 will now accept a new command.
3.4.3
Operation
Sending the “Halt B” (HLTB) command (with a matching PUPI) after an ATQB response places
the PICC in the Halt State. A PICC in the Halt State will only respond to a WUPB command.
PICCs in the Active State or already in the Halt State are not permitted to answer this command.
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8586A—RFID—5/09