User's Manual

5 OPERATION
42
HF80 Transponder Reader – HSMS, Release 1.3
The physical byte order is designed to correspond as closely as
possible to the SECS-I header.
Session ID is a 16-bit unsigned integer values, which occupies bytes 0
and 1 of the header(byte 0 is MSB). Its purpose is to provide an
association by reference between control messages and subsequent
messages.
Header Byte 2 is used in different ways for different HSMS messages.
For Control Messages it contains zero or a status code. For a Data
Message it contains the W-Bit and SECS stream.
Header Byte 3 contains for control messages zero or status code. For
data messages it contains the SECS function.
P-Type is an 8 bit unsigned integer value which occupies byte 4 of the
message header and message text are encoded. Only PType = 0 is
defined by HSMS to mean SECS II message encoding. For non-zero
PType values, see "special considerations".
S-Type (Session Type) is a one-byte unsigned integer value which
occupies header byte 5.
The system bytes are used to identify a transaction uniquely among the
set of open transaction. The system bytes are also defined as in SECS-I
specific.
Value Description
0 SECS-II Encoding
1 - 127 Reserved for subsidiary standards
128 - 255 Reserved, not used
Value Description Value Description
0 Data Message 6 Linktest.rsp
1 Select.req 7 Reject.req
2 Select.rsp 8 Not used
3 Deselect.req 9 Separate.req
4 Deselect.rsp 10 Not used
5 Linktest.req 11-255 Reserved , not used