ib technology

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Supported transponder types

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

types:-

1) Hitag 1 read/write transponders configured in R/W Public mode. Setting the HT1 to

any other configuration will render them inoperable with this system. Note: Only the

HT1 ICS30 02x Hitag silicon is fully supported for WRITE/ READ operations. The

earlier HT1 ICS30 01x silicon (made obsolete early 1997) is only partially supported.

2) Hitag S256, S2048 read/write transponders configured in PLAIN MEMORY mode

(factory default).

3) Hitag 2 read/write transponders configured in PASSWORD mode. Setting the HT2

transponder to any other configuration will render them inoperable with this system.

4) EM Marin EM4001/H4001 type transponders including H4003, H4102 and

compatible read-only tags with the correct header, data and parity bit structure.

5) Microchip Technology MCRF 200-I/123 RF transponders that use direct ASK

modulation, Manchester coding and with a data rate of RF/64. The MCRF200

transponder is expected to have the 0x802A header sequence at the start of the

memory array.

The operation of the MicroRWD QT with Hitag 1/S, Hitag 2, EM400X and MCRF200/123

transponders is identical to the individual MicroRWD reader versions and their operation is

fully described in this document and in the H1prot.PDF, H2prot.PDF, EMprot.PDF and

MCprot.PDF documents.

The transponder identification codes described in this text are regarded as the first four bytes

(serial number or page 0) of the H1 and H2 memory array or bytes 1 to 4 (least significant

four bytes) of the EM400X and MCRF200 memory arrays (ignoring most significant byte 0).

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 tag communication. It is assumed that the host (such

as a PC) can buffer received data.

Tx, Rx and RTS signals from the Micro RWD are all TTL level and can be converted to +/-

10v RS232 levels using an inverting level converter device such as the MAX202 (note the

inversion of the TTL levels).

The serial communication system and protocol allows for a 10ms ‘window’ every Tag polling

cycle indicated by the BUSY line being low. During this ‘window’ the host must assert the

first start bit and start transmitting data. The BUSY goes high again 10ms after the last stop

bit is received. NOTE that only one command sequence is handled at a time.