The AT49BV642D(T) is a 2.7-volt 64-megabit Flash memory organized as 4,194,304 words of 16 bits each. The memory is divided into 135 sectors for erase operations. The device can be read or reprogrammed off a single 2.7V power supply, making it ideally suited for in-system programming. To increase the flexibility of the device, it contains an Erase Suspend and Program Suspend feature. This feature will put the erase or program on hold for any amount of time and let the user read data from or program data to any of the remaining sectors. The end of program or erase is detected by Data Polling or toggle bit. The VPP pin provides data protection and faster programming times. When the VPP input is below 0.4V, the program and erase functions are inhibited. When VPP is at 1.65V or above, normal program and erase operations can be performed. With VPP at 10.0V, the program (dual-word program command) operation is accelerated. A six-word command (Enter Single Pulse Program Mode) to remove the requirement of entering the three-word program sequence is offered to further improve programming time. After entering the six-word code, only single pulses on the write control lines are required for writing into the device. This mode (Single Pulse Word Program) is exited by powering down the device, by taking the RESET pin to GND or by a highto-low transition on the V PP input. Erase, Erase Suspend/Resume, Program Suspend/Resume and Read Reset commands will not work while in this mode; if entered they will result in data being programmed into the device. It is not recommended that the six-word code reside in the software of the final product but only exist in external programming code.