24. However, the ability of the user to
manipulate each of the individual ?¬?elds in the response is intact. Therefore, the response
customization along with the corresponding state changes can increase in complexity
with ease.
Query command
QCmd DR M TRext Sel Session Target Q CRC-5
4 bit 1 bit 2 bit 1 bit 2 bit 2 bit 1 bit 4 bit 5 bit
Response
RN16
16 bit
Ack command
AC md RN
2 bit 16 bit
Response
PC EPC CRC-16
16 bit 96 bit 16 bit
Req _RN command
Cmd RN CRC-16
8 bit 16 bit 16 bit
Response
RN CRC-16
16 bit 16 bit
Write command
Cmd Mem Bank Word Ptr Data RN CRC-16
8 bit 2 bit 8 bit 16 bit 16 bit 16 bit
Response
Header RN CRC-16
1 bit 16 bit 16 bit
FIGURE 3.21
Selected primitives and response formats from ISO 18000 Part 6C.
50 RFID Handbook: Applications, Technology, Security, and Privacy
3.4.3 Compiler-Generated RFID Tag Program
The code generation is the ?¬?nal compiler phase determined by the tag behavior and the
input macros speci?¬?cation. Code generation can be in the form of ANSI-C for generalpurpose
microprocessor controllers or VHDL in the case of hardware controllers. The
decode instructions generated by the compiler identify the received RFID primitive. For
each incoming command, routines are generated by the compiler that unpack the command
generating the ?¬?elds that it is expected to contain. The corresponding behavior is
attached to each ?¬?eld, and the corresponding routines for packing the response are then
generated.
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