
AT88RF1354 SPI User Guide For CryptoRF
Figure 3.
Detail Example – Serial Communications with the SPI Interface
String Decode > O0006 Host sends six bytes thru microcontroller to AT88RF1354 serial port.
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03
AT88RF1354 TX Data command.
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02
Data bytes sent to PICC. In this example 2 bytes are sent to the PICC.
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01
PARAM. Bits[2:0] select AT88RF1354 Communication Protocol Register 1 (CPR1).
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00
Timeout. A $00 selects the Frame Waiting Interval defined during CPR initialization.
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11
To PICC: Upper nibble is CID assigned in the ATTRIB command. Lower nibble is $1.
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00
To PICC: PARAM. Upper nibble is $0 (disable anti-tearing). Lower nibble is user zone 0.
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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01
AT88RF1354 Response: PARAM. Echo PARAM byte used in prior TX Data command.
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11
PICC Response: Upper nibble is CID assigned in ATTRIB command. Lower nibble is $1.
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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.
All examples assume a microcontroller is being used as a pass-thru device between the
PC host and the reader. The microcontroller translates command and data strings from
the host into SPI format. Likewise all SPI response data from the AT88RF1354 is
translated back to strings by the microcontroller
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8586A—RFID—5/09