Removable Mother/Daughter Peripheral Card
A peripheral card having a Personal Computer (“PC”) card form factor and removably coupled externally to a host system is further partitioned into a mother card portion and a daughter card portion. The daughter card is removably coupled to the mother card. In the preferred embodiment, a low cost flash “floppy” is accomplished with the daughter card containing only flash EEPROM chips and being controlled by a memory controller residing on the mother card. Other aspects of the invention includes a comprehensive controller on the mother card able to control a predefined set of peripherals on daughter cards connectable to the mother card; relocation of some host resident hardware to the mother card to allow for a minimal host system; a mother card that can accommodate multiple daughter cards; daughter cards that also operates directly with hosts having embedded controllers; daughter cards carrying encoded data and information for decoding it; and daughter cards with security features.
1 . A method of storing user data on and retrieving user data from a non-volatile memory card, comprising:
encoding the user data,
storing both the encoded user data and information useful to decode the encoded user data on the memory card,
thereafter reading both the encoded user data and the decoding information from the memory card, and
decoding the read encoded user data by use of the decoding information read from the memory card, thereby to obtain the user data,
wherein encoding the user data includes compressing the user data, and the decoding information stored on the memory card includes a decompression algorithm.
2 . The method of claim 1 , wherein the non-volatile memory card includes a flash EEPROM array, and both the encoded user data and the decoding information are stored in the flash EEPROM array.
3 . The method of claim 2 , wherein storing includes programming both the encoded user data and decoding information into individual memory cells of the flash EEPROM array in more than two states, thereby to store more than one bit of said user data and decoding information per cell.
4 . The method of claim 1 , wherein the encoding and storing occur when the memory card is electrically connected to a first host system, and wherein the reading and decoding occur when the memory card is electrically connected to a second host system.
5 . The method of claim 4 , wherein either the encoding is accomplished by the first host system or the decoding is accomplished by the second host system.
6 . The method of claim 4 , wherein at least one of the encoding and decoding are accomplished in a memory controller function included in a mother electronic card that is removably connectable with at least one of the first and second host systems and into which the memory card is removably connectable.
7 . The method of claim 1 , wherein at least one of the encoding and decoding are accomplished in a memory controller function included in a mother electronic card to which the memory card is removably connectable.
8 . A non-volatile memory card, comprising:
a flash EEPROM array,
encoded user data stored in a first portion of the array, and
data of information useful to decode the encoded user data stored in a second portion of the array,
wherein the stored encoded user data includes compressed user data, and wherein the information useful to decode the stored encoded user data includes a decompression algorithm.