SRI4K-A3T/1GE STMicroelectronics, SRI4K-A3T/1GE Datasheet - Page 18

• Manufacturer Part Number: SRI4K-A3T/1GE
• Manufacturer: STMicroelectronics

Specifications of SRI4K-A3T/1GE

• Operating Temperature (max): 85C
• Operating Temperature Classification: Commercial
• Lead Free Status / Rohs Status: Compliant

SRI4K
Description of an Anti-Collision Sequence
The anti-collision sequence is initiated by the INI-
TIATE() command which triggers all the SRI4K de-
vices that are present in the reader field range,
and that are in INVENTORY state. Only SRI4K de-
vices in INVENTORY state will respond to the
PCALL16() and SLOT_MARKER(SN) anti-colli-
sion commands.
Table 3. Standard Anti-Collision Sequence
After each SLOT_MARKER() command, there
may be several, one or no answers from the
SRI4K devices. The reader must handle all the
cases and store all the Chip_IDs, correctly decod-
ed. At the end of the anti-collision sequence, after
SLOT_MARKER(15), the reader can start working
with one SRI4K by issuing a SELECT() command
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Step 1 Init:
Step 2
Step 3
Step 4
Step N
Step 17
Step 18
Slot 0
Slot 1
Slot 2
Slop N
Slot 15
Send INITIATE().
– If no answer is detected, go to step1.
– If only 1 answer is detected, select and access the SRI4K. After accessing the
– If a collision (many answers) is detected, go to step2.
Send PCALL16().
– If no answer or collision is detected, go to step3.
– If 1 answer is detected, store the Chip_ID, Send SELECT() and go to step3.
Send SLOT_MARKER(1).
– If no answer or collision is detected, go to step4.
– If 1 answer is detected, store the Chip_ID, Send SELECT() and go to step4.
Send SLOT_MARKER(2).
– If no answer or collision is detected, go to step5.
– If 1 answer is detected, store the Chip_ID, Send SELECT() and go to step5.
Send SLOT_MARKER(3 up to 14) ...
– If no answer or collision is detected, go to stepN+1.
– If 1 answer is detected, store the Chip_ID, Send SELECT() and go to stepN+1.
Send SLOT_MARKER(15).
– If no answer or collision is detected, go to step18.
– If 1 answer is detected, store the Chip_ID, Send SELECT() and go to step18.
All the slots have been generated and the Chip_ID values should be stored into the
reader memory. Issue the SELECT(Chip_ID) command and access each identified
SRI4K one by one. After accessing each SRI4K, switch them into DESELECTED or
DEACTIVATED state, depending on the application needs.
– If collisions were detected between Step2 and Step17, go to Step2.
– If no collision was detected between Step2 and Step17, go to Step1.
SRI4K, deselect the tag and go to step1.
A new SRI4K introduced in the field range during
the anti-collision sequence will not be taken into
account as it will not respond to the PCALL16() or
SLOT_MARKER(SN) command (READY state).
To be considered during the anti-collision se-
quence, it must have received the INITIATE()
command and entered the INVENTORY state.
Table 3.
collision sequence. (See
ple.)
containing the desired Chip_ID. If a collision is de-
tected during the anti-collision sequence, the
reader has to generate a new sequence in order to
identify all unidentified SRI4K devices in the field.
The anti-collision sequence can stop when all
SRI4K devices have been identified.
shows the elements of a standard anti-
Figure 24.
for an exam-