
AT88RF1354 SPI User Guide For CryptoRF
3.14.2 Example
String Decode > O0009 Host sends nine bytes thru microcontroller to AT88RF1354 serial port.
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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.
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02
PARAM. Bits[2:0] select AT88RF1354 Communication Protocol Register 2 (CPR2).
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00
Timeout. A $00 selects the Frame Waiting Interval defined during CPR initialization.
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1C
To PICC: Check Password Command. Upper nibble is CID assigned in ATTRIB command. Lower nibble is $C.
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07
To PICC: Password Index (PW). A $07 selects Password Write 7.
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30
To PICC: PW1. Password byte 1 for a 1K, 2K and 4K bit CryptoRF = $30.
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1D
To PICC: PW2. Password byte 2 for a 1K, 2K and 4K bit CryptoRF = $1D.
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D2
To PICC: PW3. Password byte 3 for a 1K, 2K and 4K bit CryptoRF = $D2.
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.
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I0006 Host gets six bytes from AT88RF1354 buffer.
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00
AT88RF1354 Response: $00 (No RF communication error bits set in the EREG register).
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03
AT88RF1354 Response: PICC response byte count.
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02
AT88RF1354 Response: PARAM. Echo PARAM byte used in prior TX Data command.
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1C
PICC Response: Upper nibble is CID assigned in ATTRIB command. Lower nibble is $C.
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00
PICC Response: PICC ACK/NACK. ACK is $00, the command executed correctly.
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00
PICC Response: PICC status code. Status message $00 is no 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.
3.14.3 Operation
To read or write data in User Zones that require a password for access the host must carry out a
password validation operation. The host uses the Check Password command to send the
password for validation against the password selected with the Password Index byte. Only
PICCs in the Active State are permitted to answer this command.
If the Check Password is successful, the Password Attempts Counter (PAC) is cleared and the
ACK response is issued. Only one password is active at any time. If the Check Password fails,
the PAC is incremented and a NACK response is issued. The Check Password success or
failure is memorized and active until the PICC is powered down, removed from the Active State,
or until a new Check Password command is received. If the password trials limit is reached,
subsequent Check Password commands will be rejected.
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8586A—RFID—5/09