ISO15693 datasheet(13/45 Pages) FUJITSU

13 / 45 page

MB89R118

FRAM Data Protection if Power Lost During Data Writing

If the power to FRAM is lost while data is being written to it, data may take on unexpected values, possibly

adversely affecting system operation.

The MB89R118’s FRAM is accessed (updated) in byte units.

The MB89R118 circle confirms that the level of power supply voltage is sufficient before data is written to each

byte.

However, since write commands access more than one byte at once a power loss in the middle of write commands

may result in a mixture of new written data and still remaining old data. As a result, confirm success of a write

command with read command after each write command.

Requests/Responses

A request is sent from the reader/writer to the transponder. In reply to the request, the transponder sends a

response to the reader/writer.

Each request, and each response, is transmitted in a single frame.

• Structure of requests and responses

A request consists of the following 5 fields :

•Flag

• Command code

• Parameter (required or optional depending on the command)

• Application data

•CRC

A response consists of the following 4 fields :

•Flag

• Parameter (required or option depending on the command)

• Application data

•CRC

Each byte is transferred, beginning with the lowest bit. When two or more bytes are transferred, transfer begins

with the lowest one.

Set the RFU_flag always to “0”.

Operating Modes

The MB89R118 has the following 3 operating modes :

Each mode specifies a different mechanism for how the transponder returns a response in reply to a request

from the reader/writer :

• Addressed mode

The MB89R118 enters addressed mode when the Address_flag is set to “1”.

In addressed mode, a request includes a UID (the Address_flag is set to “1” simultaneously), and only the

transponder that matches the UID in the request returns a response. If no transponder that matches the UID

exists, a response is not returned.

ISO15693 Datasheet(PDF) 13 Page - fujitsu semiconductor