cr95hf won't pole after idel command

[MUnge]

Hi i am using an cr95hf. After using an idel command and waking up afterwards any command I send after the idle wont work. I don't even get a polling response. Unfortunately I can't find anything in the cr95hf datasheet telling me if i need to reset or anything similar after exiting the idle mode. Also I am using the cr95hf as the plug and it is connected to an atmega 128 and I am communicating via SPI.

[MUnge]

Hey Brian,

if the X-Nucleo-NFC03A1 is needed it shouldnt be a problem to get it.

We have switched back to the built in antenna and I looped over possible dac windows and got resulst for reading up to 2.5 cm with 14443A. I am now trying to finetune the dac values so it'll only return tag detected when that is actually true, but still is able to measure at least 2 cm(I think we won't really need much more than that.).

I did the calibration on a table with a metal frame but it was at elast 15 cm away from that so I dont think that interfered. I just did the calibration again on a different table and got the same results so I don't think that awas the problem.

I downloaded the STM32CubeExpansion_NFC3_V2.0.0 and will take a look at the abstraction layer. However I think we wont really need to upgrade to a higher performing chip.

I will conntect our distributer about the Nucleo board.

Have you had any success with trying measurements on the plug-cr95hf-b?

best Michael

[MUnge]

Hi,

I have another Question. For our application we want to use the hibernate state as well as the idle(tag detection) state. When using the command 0x07 0E 08 04 00 04 00 18 00 00 00 00 00 00 00 00

which is supposed to give me the hybernate state we measure the same supply current as in the tag detection. As a reference we measured the current when our board was powered but the chip not woken yet by an irq_in and got a significant lower value as with either of the idle commands. Is there another option to get to such a low power state or is my command maybe wrong?

Best Michael

[Brian TIDAL]

​Hi Michaël,

I've not yet have received a PLUG-CR95HF-B. I hope to have it this week.

Regarding the hibernate state, I've done some tests on my side. I've put an ammeter on the 3V3 input of the nucleo expansion board (measuring the overall consumption on the expansion board). I can see a significant consumption drop when entering Hibernate state (10.6 µA) vs. Tag Detector state (221µA average). Of course, these values are not significant as I measure the overall consumption on the expansion board but this is proving that the hibernate state is working. I've used the same hibernate command as the one you used. Make sure to measure only the reader part (i.e. make sure not to have your MCU in the consumption path).

On my side, for the overall expansion board:

• Power-up state: 330 µs
• Ready state: 280 µA
• Tag detector state: 221 µA (average)
• Hibernate state: 10.6 µA

Rgds

BT

[Brian TIDAL]

HI Michaël,

I've done some read range tests with  a PLUG-CR95HF-B.

I confirm that the read range results are better when using an X-NUCLEO-NFC03A1than when using  a PLUG-CR95HF-B

On PLUG-CR95HF-B, I reach 6.9 cm max read range for ISO15693 tag whereas I can reach 9.2 cm with X-NUCLEO-NFC03A1. With ISO14443A, I can reach about 2.8 cm on PLUG-CR95HF-B.

Rgds

BT