The AT91SAM7S256D-AU is a SAM7S series 32-bit Flash Microcontroller based on the 32-bit ARM7TDMI RISC processor. It operates at a maximum speed of 55MHz and features 256kB of flash memory and 64kB of SRAM. The embedded flash memory can be programmed in-system via the JTAG-ICE interface or via a parallel interface on a production programmer prior to mounting. Built-in lock -bits and a security -bit protect the firmware from accidental overwrite and preserves its confidentiality. The SAM7S Series system controller includes a reset controller capable of managing the power-on sequence of the microcontroller and the complete system. Correct device operation can be monitored by a built-in brownout detector and a watchdog running off an integrated RC oscillator. The multi-layer bus matrix, multiple SRAM banks, PDC and DMA support parallel tasks and maximize data throughput.