
AT88RF1354 SPI User Guide For CryptoRF
3.6.2
Example
String Decode > O0008 Host sends eight bytes thru microcontroller to AT88RF1354 serial port.
>
03
AT88RF1354 TX Data command.
>
04
Data bytes sent to PICC. In this example 4 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.
>
12
To PICC: Read Command. Upper nibble is CID assigned in ATTRIB command. Lower nibble is $2.
>
00
To PICC: $00
>
00
To PICC: ADDR. Starting address of location to be read.
>
03
To PICC: "L". L is the number of bytes to read minus 1.
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.
> I000A Host gets ten bytes from AT88RF1354 buffer.
>
00
AT88RF1354 Response: $00 (No RF communication error bits set in the EREG register).
>
07
AT88RF1354 Response: PICC response byte count.
>
01
AT88RF1354 Response: PARAM. Echo PARAM byte used in prior TX Data command.
>
12
PICC Response: Upper nibble is CID assigned in ATTRIB command. Lower nibble is $2.
>
00
PICC Response: PICC ACK/NACK. ACK is $00, the command executed correctly.
>
11
PICC Response: Data 1
>
22
PICC Response: Data 2
>
33
PICC Response: Data "L"
>
44
PICC Response: Data "L+1"
>
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.
3.6.3
Operation
The Read User Zone command reads data from the device’s currently selected User Zone. The
data byte address is internally incremented as each byte is read from memory. If the data byte
address is incremented beyond the end of the current zone during a read, then the address will
“roll over” to the first byte of the same zone. Only PICCs in the Active State are permitted to
answer this command.
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8586A—RFID—5/09