www.ams.com

Revision 1.0

15 - 42

AS3953

Datasheet - D e t a il e d D es c r i pt io n



TC(1): The interface byte TC(1) specifies a parameter of the protocol. The interface byte TC(1) consists of two parts:

- The most significant bits

b8 to b3 are set to 000000, all other values are ‘RFU’.

- The bits

b2 and b1 define which optional fields in the prologue field are supported by the PICC. The PCD is allowed to skip fields that are

supported by the PICC. Bit

b2 indicates support of CID and b1 indicates support of NAD. The AS3953 value is ‘10’ indicating “CID

supported” and “NAD not supported”.

Table below defines the coding of the TC(1) byte.

7.6 Proprietary Commands

Proprietary commands have the same format as blocks defined in ISO 14443-4 with the difference that optional NAD field is abandoned since

NAD is not supported by the AS3953. The same format is used for commands sent by PCD and AS3953 responses. Table below defines the

coding of the Proprietary commands.

Prologue field consists of the mandatory Protocol Control Byte and an optional Card Identifier Byte. Card identifier byte is according to ISO

14443-4 definition. Epilogue field contains CRC over transmitted block.

Prologue Field for Proprietary Commands.

Table below defines the coding of Prologue field for Proprietary commands.

The following proprietary commands are implemented:



Wake-up: Sends a wake-up interrupt to controller



Read EEPROM: Reads data from EEPROM



Write EEPROM: Writes data to EEPROM

Wake-up Command.

Information field of

Wake-up command consists of one byte only (see table below). The AS3953 echoes back the same information field.

Table below defines the coding of the AS3953 reply INF to

Wake-up command.

b8

MSB

b7

b6

b5

b4

b3

b2

b1

LSB

Description

0

0

0

0

0

0

1

0

Coding of ATS byte TC(1)

CID

NAD

Prologue Field

Information Field

Epilogue Field

PCB

[CID]

INF

EDC

1 byte

1 byte

2 bytes

Bit

Value

Function

b8

0

01 indicates proprietary command

b7

1

b6

0

Shall be set to this value, other values are ‘RFU’

b5

1

b4

CID following if bit is set to ‘1’

b3

1

Shall be set to this value, other values are ‘RFU’

b2

0

b1

1

01h

1byte

01h

1byte