Does HDX+ have Collision Avoidance Capability?

Update ... great news ... got two EVM's  and both "worked straight out the box"...Win7/32bit system

Things to watch for other members

1.  "Round cattle" Read-Only ear-tags.... MUST not get closer to the Reader coil than about 20mm...closer and reader says no Transponder Detected" (de-tuning?)

2. The above tags are recognized about 100-150 mm away ... ie on LF/HDX+ tab ... <"Check Tag' + "Continuous" + "ReadTag"> buttons all on for this, is good.

3. If more than one tag near reader Aerial... display says "Multiple Transponders'... this is real neat stuff.(FM CaptureEffect ...collision avoidance coming louder here now!!!)

4. Resonance "seems" to work equally well for older RO tags ie nonHDX+.... what a bonus.

5. My confidence is restored...I have a great tool here.

NOW the sting... I have access to many thousands of 'used tags" ....some/many of these were reported as being undetectable by long-Range Panel readers (us).

Lot of angry people out there who blame "us" for non reads...but they are readable with Close-Up-hand-Readers" ....of course you say, it's obvious now.

We knew ahead of time by deduction the most probable cause for these "problem tags" was they were "OFF TUNE"... but no real way to say confidently ...but now we do.

Already I have found "All of my small here sample lot" (8) are reporting typically as being 135.5kHz(+/- 500Hz) ... we expected 134.2 but now HDX+ should fix this someday!

When I return to factory, we will test "every available" tag we have and i will give you our results ... maybe they meet ISO requirement, I will recheck this "get out of jail clause again soon"

Sure a percentage are "off-tune" due to physical violence or abrasion.... let's say half are in this group!

Now ...we also have many "recent made new tags (orange coded not HDX+) ...and already with the few I have with me here (4) .... they are all very close to 134.6Khz ...this is good. Seems someone got better at making the silicon/coils of the free running HDX Transponders???

Somewhere I recall the cattle HDX+ tags should be "bench-tuned" to about 139khz (need help on this recollection)....this being the case, then when tag is attached to

the beast, the free-space tuning should/probably detune itself "down" to closer to 134.2khz.

To test this with the use of my new EVM, I hold a tag tightly in my fist and present it for Frequency....in all cases the tag frequencies "fall by about 150 Hz...rough

test but proves a point...Tags that are injected under the skin (not for us) probably de-tune a lot more... the Bolous tag that are swallowed into the beasts stomach also 

probably de-tune much more.

Some tag manufacturers use the Glass capsule and encapsulate into something that resembles a "button-earTag" ...good on them... great for sheep!

nb...any proposal to use  a PLL receiver as quick solution is doomed ...just too many in detection volume simultaneously...etc.

So, I am happy.... all I need now is for someone to speak to me about what is or is not happening with "data collisions'... keep in mind we only have a narrow time-portal

about 300mS during which time the beast passes in then out of the detection volume ...never to be seen again...so arbitration had better be pretty good.

can you see now why we are anxious....no surprises please, let us know now....please

Kind regards

Ray

Concerning my interest/persistence with Data collision avoidance for HDX animal tags.

I am still researching this ... but I need help.

I understand there is some appended part to ISO-11784/5 documents which "may" speak to this matter?

I will track it down, but if other forum members been there before me, some guidance will help,

A visit to this link page will show those interested that a "feature" like Collision avoidance
through some form of "speakback/wait till you are asked" is already implemented in some new or as
they call the "advanced HDX" transponders.

http://www.sic.co.th/product_ic_detail.php?p_id=22&s_id=7&m_id=1

The coil tuning/trimming (once electronics is encassed...TI call this HDX+) is also being
implemented by other RFID chip manufacturers.

My above posts, speak to my interest on this matter, my hope is some one in TI can either calm me
or dismiss me on this matter?

The best I can deduce from my scant research, is that after the classic 128 bit telegram, resides
a "new" additional memory space, into which the user can "burn in" his own secret password (800 bit storage?)

These "new/enhanced/nextgeneration???" HDX+ transponder chips just act as normal R/O devices
(for backward compatibility?) until the Reader emits a special (OOK?) code during the charge duration...

I suspect some similarity with ISO 1593/14333 protocols may be involved...do not know.

Am I chasing shadows here ?...any guidance from any observer here would be appreciated.

Kind regards

Ray

At last ...

www.iso.org/iso/livelinkgetfile-isocs?nodeId=15545800

Ray

Hi Ray, we have prepared the new MRD2EVM so it will be capable detecting HDX tags with advanced features suporting ISO14223/18000-3 protocols. At the moment such parts are not available, but we will keep you and the community updated, and I am sure you will also check the TI RFID web page from time to time to time....

Best regards,

KSA