HTMS1x01_8x01 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2015. All rights reserved.
Product data sheet
COMPANY PUBLIC
Rev. 3.4 — 21 May 2015
152934 29 of 57
NXP Semiconductors
HTMS1x01; HTMS8x01
HITAG µ transponder IC
13.4 Modes
13.4.1 ISO 11785 Mode
This mode is also named TTF (Transponder Talks First).
Every time a transponder IC is activated by the field it starts executing this mode. After
waiting the maximum listening window time (see Section 11.2
) the transponder IC sends
continuously its TTF data (128-bit).
The TTF data stored in the memory will be not checked for ISO compliance, therefore
data will be sent as stored in the EEPROM.
Receiving a valid command or a switch command within the listening window sets the
transponder IC into RTF (Reader Talks First) mode.
13.4.2 RTF Mode
In this mode the transponder IC reacts only to RWD request commands as presented in
Section 14
. A valid request consists of a command sent to the transponder IC being in
matching state (therefore see tables in Section 14
and transponder ICs state machine in
Section 13
).
13.4.3 Anticollision
The RWD is the master of the communication with one or multiple transponder ICs. It
starts the anticollision sequence by issuing the inventory request (see Section 14.3
).
Within the RWD command the NOS flag must be set to the desired setting (1 or 16 slots)
and add the mask length and the mask value after the command field.
The mask length n indicates the number of significant bits of the mask value. It can have
any value between 0 and 44 when 16 slots are used and any value between 0 and 48
when 1 slot is used.
The next two subsections summarize the actions done by the transponder IC during an
inventory round.
13.4.3.1 Anticollision with 1 slot
The transponder IC will receive one ore more inventory commands with NOS = '1'. Every
time the transponder ICs fractional or whole UID matches the mask value of RWD's
request it responses with remaining UID without mask value.
Transponder ICs responses are modulated by dual pattern data coding as described in
Section 11.4
.
