
AT88RF1354 SPI User Guide For CryptoRF
1.4.1
SPI Command Format
Each command example shown in this document is presented in two formats. First each
command is shown as a high level illustration (Figure 2). This illustration shows high level byte
information plus processing and signaling information. RF transmissions are denoted by a green
text box. Reader and PICC response bytes are shown below the blue text box.
All command/response examples in this document assume the Host initiates communication by
sending a command string from its serial port. A microcontroller intercepts the Host’s command
string and converts the string into SPI format. The SPI formatted command is then passed to the
AT88RF1354 SPI interface. The Host’s command string is shown in the left-most column.
The reader processes the SPI formatted command passed to it from the microcontroller. The
reader’s actions are shown in the middle column.
The CryptoRF PICC processes commands received from the reader. The PICC response is RF
transmitted back to the reader. PICC actions and responses are shown in the right-most column.
The PICC response is processed by the reader. When processing is complete, the AT88RF1354
ISTAT line goes high to indicate data is ready. The AT88RF1354 will not accept additional
commands when ISTAT is high. The AT88RF1354 data buffer must be emptied before
continuing. Empty the data buffer by clocking data out the SPI interface.
Depending upon the command, a response may be generated from just the reader or the
response may include data bytes from both the reader and the PICC. The bytes are shown in the
order in which they are sent and transmitted.
Following each illustration is a detailed description of the command and response string (Figure
3). Command strings sent from the Host to the reader are preceded by the letter “O”. Responses
received by the Host are preceded by the letter “I”.
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