ST25R3911B datasheet(28/116 Pages) STMICROELECTRONICS

28 / 116 page

Command

code (hex)

Command

Comments

Command

chaining

Interrupt after

Termination

Operation

mode (1)

Clear RSSI

Clears RSSI bits and restarts the

measurement

Yes

Transparent mode

Amplitude of signal present on RFI inputs is

measured, result is stored in A/D converter

output register

Yes

Calibrate capacitive

sensor

Calibrates capacitive sensor

Yes

See note(4)

Measure capacitance

Perform capacitor sensor measurement

Yes

See note(5)

Measure power

supply

Yes

Start general purpose

timer

Yes

Start wake-up timer

Yes

All except wu

Start mask receive

timer

Yes

See note (6)

Start no-response

timer

Yes

en, rx_en

Test access

Enable /W to test registers

Yes

All

Other Fx

Reserved for test

Other codes

Not used

1. Defines the bits of the Operation control register that have to be set in order to accept a particular

command.

2. After termination of this command I_cat or I_cac IRQ is sent.

3. This command is not accepted in case the external definition of the regulated voltage is selected in the

Regulator voltage control register (bit reg_s is set to high).

4. Accepted in all modes in case bit cs_mcal of the Capacitive sensor control register is set to 0. It is

recommended to execute this command in Power-down mode.

5. Accepted in all modes, it is recommended to execute this command in Power-down mode.

6. Accepted only in the Initial NFC Active Target Communication Mode.

Set default

This direct command puts the ST25R3911B in the same state as power-up initialization. All registers are initialized

to the default state. The only exceptions are for I/O IO configuration register 1, IO configuration register 2 and

Operation control register (not affected by Set default command) that are set to default state only at power-up.

Note:

Results of different calibration and adjust commands are also lost.

This direct command is accepted in all operating modes. In case this command is sent while en (bit 7 of the

Operation Control register) is not set FIFO and FIFO status registers are not cleared.

Direct command chaining is not allowed since this command clears all registers.

IRQ due to termination of direct command is not produced.

Clear

This direct command stops all current activities (transmission or reception), clears FIFO, clears FIFO status

registers and stops all timers except Wake-Up timer. If bit nrt_emv in the General purpose and no-response timer

control register is set to 1, the No-Response timer is not stopped. If nfc_ar in the Mode definition register is set to

1, the internal timer for the Response RF Collision Avoidance is not stopped and the Response RF Collision

Avoidance will take place once this timer epxires. Set nfc_ar to 0 prior to sending the direct command Clear to

stop any Response RF Collision Avoidance activity too. It also clears collision and interrupt registers. This

command has to be sent first in a sequence preparing a transmission before writing data to be transmitted in

FIFO (except in case of direct commands Transmit REQA and Transmit WUPA).

ST25R3911B

Application information

DS11793 - Rev 6

page 28/116

ST25R3911B 数据表(PDF) 28 Page - STMicroelectronics

ST25R3911B 数据表(HTML) 28 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载

链接网址

ST25R3911B 数据表(PDF) 28 Page - STMicroelectronics

ST25R3911B 数据表(HTML) 28 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表 下载

链接网址

数据表下载