ib technology

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Default RWD EEPROM parameter settings:

Byte 0: 0x60,

260mS Polling delay / SLEEP period

Byte 1: 0x55

RF ON

Byte 2: Reserved

Byte 3: 0x01

EM4102 Reader mode

Byte 4: 0x03,

Aux data output as 9600 baud serial on OP0

Byte 5: 0x00

Weigand NO parity option, only used if Byte 4 = 0x01 / 02

Byte 6: 0x00

Aux data “plain” as read from card (byte order NOT reversed)

Byte 7: 0x00

“Beep” output delay OFF

Byte 8: 0x00

Aux output (serial data) directed to OP0 pin.

Addition Notes for Commands

NOTE also that for the “READ TAG” command, if an error flag has been set in the

Acknowledge code then there will be NO following data.

NOTE that the serial communication uses hardware handshaking to inhibit the host from

sending the Micro RWD commands while Card communication is in progress. The serial

communication system and protocol allows for a 6ms ‘window’ every Card polling cycle

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

first start bit and start transmitting data. The CTS/BUSY goes high again 6ms after the last

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

between the CTS pulses (polling delay) can have three rates depending on whether a card is

present or not and if commands are being received by the RWD

NOTE that the commands and parameters must be sent to the RWD with no gaps otherwise

communication timeout occurs and the RWD enters the polling delay period (the command

string would then be incomplete and an RS232 error is flagged).

NOTE that the MicroRWD EM4102 LP version performs fast polling cycles as long as there

are commands to be processed. As soon as the commands stop being sent or the gap between

sending commands is too long then timeout occurs and the polling delay increases to 100ms

(if the card is still present) or the typically longer period (as set by EEPROM parameter) if

there is no card. This is to allow repeated commands to be handled quickly such as for a

“complete card read” where repeated Read Block commands are sent to the RWD.

Commands sent infrequently will have the full polling delay between each CTS/BUSY

period.