ib technology

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2) Standalone mode is where the Mifare card identity codes (serial numbers) are checked

against a stored list of authorised codes. If an identity code is matched, the output

drives and Green LED are enabled. Effectively standalone mode occurs when there is

no host system communicating with the Micro RWD. Up to 60 serial numbers can be

stored in the authorisation list so this mode of operation can be used to create a “mini

access control” system.

The automatic auxiliary outputs can also be used to send serial number or other card

memory block data to a controller with no command interaction required.

Supported transponder types

The MicroRWD MF is designed to communicate with the following passive RF transponder

types. Note that Mifare cards and transponder devices are fabricated by several companies

under licence from Philips/NXP Semiconductors. They are all fully Mifare compliant and

only differ in having different default Security Keys loaded in the factory:-

1) Mifare standard 1k card (MF1 IC S50 transponder) and Infineon equivalent.

2) Mifare standard 4k card (MF1 IC S70 transponder)

3) Mifare Ultralight card (MF0 IC U1 transponder)

4) Mifare ProX, Smart MX (JCOP) dual-interface card types are supported to allow

single or double UID to be acquired and “Mifare” operations performed across the

contactless interface. DESFire, Mifare PLUS supported for serial number acquisition.

5) Any ISO 14443A compliant contactless card can be accessed for Serial Number. Full

Read/Write access will only be possible if card fully supports Philips/NXP

Semiconductors CRYPTO1 algorithm and encrypted data protocols.

The operation of the Micro RWD MF and the Mifare transponders is described in more detail at

the end of this document.

The identification codes described in this text are regarded as the four-byte Mifare SINGLE

UID (Unique Identifier/serial number) or the least significant four bytes of the seven-byte

Ultralight DOUBLE UID.

Serial Interface

This is a basic implementation of RS232. The Micro RWD does not support buffered

interrupt driven input so it must control a BUSY (CTS) line to inhibit communications from

the host when it is fully occupied with card communication. It is assumed that the host (such

as a PC) can buffer received data. This CTS signal must be connected to the host computer

communication port to allow “hardware handshaking” or the host driver software must check

the CTS signal and only send commands/data when it is in a LOW state. The CTS signal is

pulsed LOW for a 6ms period each polling cycle. The host computer must wait for this LOW

signal and then send the command and data.