Abstract: The existing ATM systems uses one magnetic card & a static PIN. Hence the security of present system is vulnerable as security of such systems can be breached by skimming devices, card trapping etc. The proposed system introduces transaction authentication code (TAC) which is dynamic 4 digit secrete code generated during transaction in addition with static PIN and send it to userís cell phone no. Here unless entered code by the user as well as generated code is matched the transaction doesnít get completed. This system is realized using LPC2148 which is a series controller of ARM 7 & peripherals like GSM module & RFID systems. Proposed system is complex and hence provides better security than systems before.

Keywords: ATM, ARM7 LPC2148, TAC, GSM Modem, LCD, RFID Cards and Reader, Keypad.