The OXCF950 rev B is a low cost asynchronous 16-bit PC card (henceforth referred to as PCMCIA) or Compact Flash (henceforth referred to as CF) UART (and Local Bus) device. Local Bus Selection is performed by use of a MODE pin. Note that Local Bus mode uses indirect addressing, which is only supported by PCMCIA. The 3.3V technology has been specified to operate as low as 2.7 V to allow an in-line regulator to be used for mixed 3V/5V applications. All the I/Os are 5V tolerant with the exception of the clock/crystal oscillator input. The EEPROM interface allows the programming of the Attribute Memory, UART and Local Configuration Registers during power up or hard/soft reset. This allows different card manufacturers to modify the information contained in the Attribute memory or UART/registers as required, for example PC-Card ID value.