The DS5250 is a highly secure, 4 clocks-per-machine cycle, 100% 8051-instruction-set-compatible microprocessor in the Secure Microcontroller family from Dallas Semiconductor. It was designed to be the cryptographic engine of PIN pads, financial terminals, and any other application in which data security is paramount. A key feature of the device is that it encrypts its program memory with a hardware-based single or triple (3) DES (data encryption standard) algorithm, making it nearly impossible to extract information. Another DES (3DES) hardware block is available to the user for encrypting arbitrary information in data memory space. This makes the device ideal for storage and transmission of passwords, personal identification numbers, encryption keys, and other highly confidential information.