Method and apparatus for upgrading reprogrammable memory contents in a PCMCIA card

Claim 2

A removable computer card including stored Card Information Structure (CIS) information that defines an interface with said card in a computer system, comprising: (a) a specialized single port random access memory (SPRAM) device having a first portion for storing said CIS information, and a second portion for storing data and instructions, said SPRAM device having a write enable input to allow write access to said first and said second portions, said SPRAM including an input for a host data bus; (b) a plurality of control storage locations coupled to said SPRAM device, each having access control data stored therein; and (c) a controller coupled to said SPRAM device and said storage locations through a micro-controller databus, said controller controlling access requests by said computer system to said SPRAM device, and setting said control data in said storage locations responsive to said computer system to enable said computer system to read and write to said SPRAM device, said controller executing an unlock logic routine responsive to a write request by said computer system to enable said write enable input that allows said computer system to write to said SPRAM device and altering either said first portion or said second portion.

Claim 3

The computer card of claim 1, wherein said SPRAM device has a first mode in which said access control signal is asserted by said controller to allow said computer system read-only access to said SPRAM device, and a second mode in which said access control signal is deasserted to allow said computer system read and write to said SPRAM device.

Claim 4

The computer card of claim 1 further comprising a reset mechanism for resetting each of said plurality of control storage locations upon initially powering up each of said plurality of control storage locations.

Claim 5

The computer card of claim 1 wherein said controller includes circuitry that enables control data in a first of said plurality of said control storage locations to be set responsive to an access request by said computer system.

Claim 6

The computer card of claim 1 wherein said controller further includes circuitry that enables control data in a second of said plurality of said control storage locations to be set responsive to a write access to said SPRAM device by said computer system, said data indicating the current status of said SPRAM device.

Claim 7

The computer card of claim 1, wherein said first plurality of said storage locations includes a command register.

Claim 8

The computer card of claim 1 wherein said second plurality of said storage locations includes a status register.

Claim 9

The computer card of claim 1 wherein said controller further includes circuitry to provide control signals asserted responsive to access requests from said computer system to said SPRAM device, and wherein a first of said control signals is asserted to block write access to said SPRAM device by said computer system.

Claim 10

The computer card of claim 8, wherein a second of said control signals is asserted by said computer system to initiate a write access to said SPRAM device.

Claim 11

A removable computer card including stored Card Information Structure (CIS) information that defines an interface with said card in a computer system, comprising: (a) a specialized single port random access memory (SPRAM) means for storing information under control of a processor in said removable computer card, the SRRAM means configured to receive input via a host data bus, the SPRAM means including a first portion for storing said CIS information, and a second portion for storing data and instructions for said computer system; (b) control storage means for storing control access data, said control storage means being coupled to said SPRAM means via a microcontroller bus; (c) control means for controlling access requests to said SPRAM means by said computer system, said control means being coupled to said control storage means and said SPRAM means; and (d) an unlock logic means, responsive to write requests from said computer system, for enabling said computer system write to said SPRAM means.

Claim 12

A removable computer card including stored Card Information Structure (CIS) information that defines an interface with said card in a computer system, comprising: (a) a specialized single port random access memory (SPRAM) means for storing information under control of a processor in said removable computer card, the SRRAM means configured to receive input via a host data bus, the SPRAM means including a first portion for storing said CIS information, and a second portion for storing data and instructions for said computer system; (b) control storage means for storing control access data, said control storage means being coupled to said SPRAM means via a microcontroller bus; (c) control means for controlling access requests to said SPRAM means by said computer system, said control means being coupled to said control storage means and said SPRAM means; and (d) an unlock logic means, responsive to write requests from said computer system, for enabling said computer system write to said SPRAM means.

Claim 13

The computer card of claim 10, wherein said SPRAM means has a first and a second operating mode, and wherein in said first mode said SPRAM means allows said computer system only read access to said first portion in said SPRAM means, and in said second mode, said computer system reads and writes to said first and said second portion in said SPRAM means.

Claim 14

The computer card of claim 10 further comprising a reset means for resetting each of said plurality of control storage means upon initially powering up each of said plurality of control storage means.

Claim 15

The computer card of claim 10 wherein said control means includes a setting means for enabling a first of said plurality of said storage means to be set responsive to an access request by said computer system.

Claim 16

The computer card of claim 10 wherein said first plurality of said storage means is a command register, and a second of said plurality of said storage means is a status register.

Claim 17

The computer card of claim 10 wherein during a write access by said computer system to said SPRAM means, said computer system upgrades said CIS in said first portion of said SPRAM means.

Claim 18

The computer card of claim 10 wherein said control means includes a circuitry for providing control signals asserted responsive to requests from said computer system to said SPRAM means, and wherein a first of said control signals is asserted to disable write access to said SPRAM means by said computer system.

Claim 19

An upgradable removable computer card comprising: (a) a specialized single port random access memory (SPRAM) device, under control of a processor in said removable computer card including a first and a second portion to contain configuration information and instructions for said card, said SPRAM device including (a1) a random access memory (RAM) device including said first and second portions of said SPRAM device, said RAM device having a write enable input to enable write access to said first and second portions, (a2) a first plurality of selectors coupled to said RAM device, said first plurality of selectors selecting address requests to said RAM device, (a3) a second plurality of selectors coupled to said RAM device, said second plurality of selectors selecting data presented to said RAM device, (a4) a third plurality of selectors coupled to said RAM device, said third plurality of selectors selecting control signals to said RAM device, and (a5) a plurality of logic gates coupled to said RAM device, said plurality of logic gates logically selecting input and output signals to and from said RAM device; (b) an SPRAM control registers unit coupled to said SPRAM device, said SPRAM control registers unit containing data to control and monitor said SPRAM device; (c) a microcontroller subsystem coupled to said control registers unit, said microcontroller controlling access to said SPRAM device; and (d) an unlock logic circuit, responsive to said computer system, to enable said computer system to write to said RAM device and replace or alter said configuration information and instructions for said card.

Claim 20

An upgradable removable computer card comprising: (a) a specialized single port random access memory (SPRAM) device, under control of a processor in said removable computer card including a first and a second portion to contain configuration information and instructions for said card, said SPRAM device including (a1) a random access memory (RAM) device including said first and second portions of said SPRAM device, said RAM device having a write enable input to enable write access to said first and second portions, (a2) a first plurality of selectors coupled to said RAM device, said first plurality of selectors selecting address requests to said RAM device, (a3) a second plurality of selectors coupled to said RAM device, said second plurality of selectors selecting data presented to said RAM device, (a4) a third plurality of selectors coupled to said RAM device, said third plurality of selectors selecting control signals to said RAM device, and (a5) a plurality of logic gates coupled to said RAM device, said plurality of logic gates logically selecting input and output signals to and from said RAM device; (b) an SPRAM control registers unit coupled to said SPRAM device, said SPRAM control registers unit containing data to control and monitor said SPRAM device; (c) a microcontroller subsystem coupled to said control registers unit, said microcontroller controlling access to said SPRAM device; and (d) an unlock logic circuit, responsive to said computer system, to enable said computer system to write to said RAM device and replace or alter said configuration information and instructions for said card.

Claim 21

The card of claim 17 wherein said microcontroller subsystem includes circuitry for providing control signals which are asserted to enable and disable access requests to said SPRAM device.

Claim 22

The card of claim 17 wherein said control register unit includes a command register the contents of which are set to activate said SPRAM device to be accessed.

Claim 23

The card of claim 17 wherein said control register unit further includes a status register for monitoring the current status of said SPRAM device in order to determine whether said SPRAM device is accessible or inaccessible.

Claim 24

An upgradable removable thin form factor computer card containing configuration information, said card comprising: (a) a specialized single port random access memory (SPRAM) device having a first and a second portion to contain upgradable configuration information and instructions for said card, said SPRAM device including (a1) a random access memory (RAM) device comprising said first and second portions of said SPRAM device, said RAM device having a write enable input to enable write access to said first and second portions (a2) a first plurality of selectors coupled to said RAM device, said first plurality of selectors selecting address requests to said RAM device, (a3) a second plurality of selectors coupled to said RAM device, said second plurality of selectors selecting data presented to said RAM device, (a4) a third plurality of selectors coupled to said RAM device, said third plurality of selectors selecting control signals to said RAM device, (a5) a plurality of logic gates coupled to said RAM device, said plurality of logic gates selecting input and output signals to and from said RAM device, and (a6) a plurality of address decoders coupled to said RAM device, said plurality of address decoders decoding addresses; (b) an SPRAM control registers unit coupled to said SPRAM device, said SPRAM control registers unit containing data to control and monitor id SPRAM device; (c) a microcontroller subsystem coupled to said control registers unit, said microcontroller subsystem controlling access to said SPRAM device; and (d) an unlock logic circuit, responsive to said computer system, to enable said computer system to write or replace CIS information in said RAM device.

Claim 25

An upgradable removable thin form factor computer card containing configuration information, said card comprising: (a) a specialized single port random access memory (SPRAM) device having a first and a second portion to contain upgradable configuration information and instructions for said card, said SPRAM device including (a1) a random access memory (RAM) device comprising said first and second portions of said SPRAM device, said RAM device having a write enable input to enable write access to said first and second portions (a2) a first plurality of selectors coupled to said RAM device, said first plurality of selectors selecting address requests to said RAM device, (a3) a second plurality of selectors coupled to said RAM device, said second plurality of selectors selecting data presented to said RAM device, (a4) a third plurality of selectors coupled to said RAM device, said third plurality of selectors selecting control signals to said RAM device, (a5) a plurality of logic gates coupled to said RAM device, said plurality of logic gates selecting input and output signals to and from said RAM device, and (a6) a plurality of address decoders coupled to said RAM device, said plurality of address decoders decoding addresses; (b) an SPRAM control registers unit coupled to said SPRAM device, said SPRAM control registers unit containing data to control and monitor id SPRAM device; (c) a microcontroller subsystem coupled to said control registers unit, said microcontroller subsystem controlling access to said SPRAM device; and (d) an unlock logic circuit, responsive to said computer system, to enable said computer system to write or replace CIS information in said RAM device.

Claim 28

The method in claim 22 wherein said step (c) includes the step of asserting a host random access memory/read only memory signal by said host computer to initiate said write access to said SPRAM device.

Claim 29

The method claim of claim 22 wherein said step (d) includes the step of enabling a write enable input of said SPRAM device to allow said computer system to write said CIS.

Claim 30

The method of claim 22 wherein said step (a) further includes setting data in a command register in said SPRAM device by said microcontroller to indicate the type of command being executed by said host computer.