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RFID card detection circuit

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Connect the RFID card reader to MCU serially. If RFID card reader gives TTL interface then connect it crossed with MCU Rx and Tx pins. If RFID card reader gives RS232 interfece then put a MAX232 between MCU Rx and Tx pins and RFID card Reader. If you are connecting the TTL way then your MCU and RFID should both work at the same voltages like 5V or 3.3V. Post the datasheet of your RFID card reader.
 
The circuit is given in the datasheet. It works a 5V but you have to give 12V to the Reader board. There is a MCU and RS232 on board. You have to interface your MCU board using a MAX232 and RS232 connector.
The control module consisting of onboard MCU controls the TMS3705A chip. You only have to do serial programming for your MCU and RS232 interface in hardware.
 
Where is SOIC pin? See the image. It is giving RS232 output. It has three pins connected to RS232 connector. The RFID board has onboard MCU and MAX232 chips. To interface your MCU to RFID board you have to use a MAX232 between your MCU and another RS232 connector which will connect to the RS232 connector on the RFID board.
 

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That`s right but where i connect pins RXD,TXD GND and VCC=12v in the attached schematic?
 

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Why are you using that circuit. It is the circuit which is on the RFID board. That circuit and a MCU and a MAX232 and a RS232 connector are all on the RFID board. You have to connect your MCU board with a RS232 connection. Don't use the circuit you posted. You have to give a 12V power supply to RFID board but the RF module and Control module on the RFID board works with 5V. The board will provide 5V from 12V.
 
I don't know. Try with baudrate starting from 1200 bps. It is not mentioned in the datasheet. The device can be connected to PC through RS232. Connect the reader to PC and try to read. See if it displays any data in hyperterminal. Try all baudrates in hyperterminal.
 
Ok thanks i am doing this.

- - - Updated - - -

Please can you send rough connections of RS232, MCU and RFID module.
 

Please let me know that i have only this circuit given in post#7 and i have not circuit given in post#6 so what should i do?

And another question is that can I interface real microcontroller to proteus RS-232 connector through COM1 Port?
 

Then you have to interface TxCTL and RxOUT pins to MCU and program the MCU. See the datasheet of TMS3705A for how to program it. Then you have to use a MAX232 between MCU and RS232 9 pin D-SUB connector which connects to PC. I don't know if Proteus accepts real hardware for serial communication instead connect your board to PC and see data in hyperterminal.
 
I directly connected the circuit to hyper terminal but when turn on the the supply only one character show on hyperterminal that is alpha,n,o and space.

MCU is must use or not.
 

You should not connect just the TMS IC to PC serial port. Your TMS chip will be burned. It works at 5V and serial port voltage will be around 12V. See the timing diagram of TMS chip. You have to put the chip in woken state for communication. It will not communicate in sleep or idle states. RF module i.e., TMS chip connects to MCU and MCU connects to MAX232 and MAX232 connects to PC through connector.

Datasheet tells only this much

INTERFACE CIRCUIT TO THE CONTROL MODULE
The control input TXCTL of the RF Module activates the transmitter if it is low level. To prevent
transmitting continuously if the line to the controller is accidentally interrupted the resistor R7 pulls up the
signal to high level. This TXCTL control line transfers the modulation signal and the Mode Control Byte. To
improve its electromagnetic susceptibility a low pass RC filter R6/C6 is introduced to this line.
The RX data output SCIO of the IC is protected against a short circuit to GND by the serial resistor R5.
In case of a very noisy environment and long signal lines between the RF Module and the Control Module
additional circuitry might be needed to avoid damaging the IC terminals by overvoltage or mal functions by
corrupted data.

Contact Texas Instruments and get some application note of TMS chip.
 
See timing diagram. You have to send a low pulse of minimum 50 us to TxCTL pin.

The wake pulse (low) must be shorter than tmcr (twake << tmcr; twake = typ 50us) to avoid that the wake pulse
is interpreted as a start of transmission.
After the wake pulse, the TXCT signal must be high for at least the maximum time of the minimum
initialization time tinit min.
The proposed timing assures that an IC in Sleep Mode will switch to IDLE state. In case the IC was
already in IDLE state, the wake pulse will not have an effect and it will remain in IDLE state.
 
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