AS3955 datasheet(74/111 Pages) AMSCO

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[v1-01] 2015-Apr-29

AS3955 − Detailed Description

Disable/Enable Transceiver

This direct command toggles internal states which enables or

disables the reception or transmission of the data. This

command should be used when MCU wants to disable the

interruption of EEPROM write/read over SPI / I²C by the received

RF wire/read command. The RF part can also be enabled by

issuing the Restart RX/TX. This command shall not change the

tag state.

Transmit Buffer

This direct command trigger the transmission of data stored in

the buffer over the RF link. Before issuing a Transmit command,

the MCU shall send a Clear Buffer command, and write into the

buffer the data to be transmitted by sending a Buffer Load

command.

Execution of this direct command is only enabled when the

AS3955 antenna coil is in a PCD field (VP_INT is above HF_PON

threshold) and AS3955 Extended or Tunneling modes are

enabled.

Transmit ACK

Transmit 4-bit ACK response.

Transmit NACK 0-5

Transmit 4-bit NACK response with different NACK codes.

Go To Sleep

Puts tag in SLEEP state. Execution of this direct command is only

enabled when AS3955 antenna coil is in a NFC device field

(VP_INT is above HF_PON threshold).

Go To Sense

Puts tag in SENSE state. Execution of this direct command is

only enabled when the AS3955 antenna coil is in a NFC device

field (VP_INT is above HF_PON threshold).

Go To Sense / Sleep

Puts tag in SLEEP state depending on the internal state of the

tag. Execution of this direct command is only enabled when

AS3955 antenna coil is in a NFC device field (VP_INT is above

HF_PON threshold).

AS3955 Folha de dados(PDF) 74 Page - ams AG