Functional Description

The xSil 269B is designed to connect an IDE/ATA device or NAND flash to USB with AES Encryption. It contains the following:

• 48-pin 9mm x 9mm LQFP package

• Single chip with integrated USB 2.0 PHY

• OnSpec?s embedded AES encryption to optionally encrypt in-bound and out-bound data

• Serial EEPROM port

• Supports NAND SLC, NAND MLC media

• Supports Spansion ORNAND

• NOP=1 support for MLC NAND

• 4-byte FEC (Forward Error Correction) in hardware (real time)

• Firmware enhancements can be stored on On-board NAND

• Serial port

• Two General Purpose Timers

• Watchdog Timer

• 16 bit Processor

• Internal RAM for supporting enhancements

• ROM with BIOS and Application code.

• Programmable Read and Write widths

• Optimum hardware controlled transfer for speed and scalability

• NAND SLC/ NAND MLC/ Spansion ORNAND

• Up to 4 Chip selects to allow extended addressing

• FEC Error detection and correction, which can correct up to 4-bytes of error per sector.

• Firmware enhancements can be stored on On-board NAND when populated.

• ROM has built in AES encryption support for SHA-256 based authentication

Embedded Encryption

The xSil 269B device has OnSpec?s embedded AES 128 bit encryption that encrypts and decrypts information. The encryption converts data to an unintelligible form and decrypting converts the data back into its original form.

Packaging

The xSil 269B is a 48-pin LQFP package.

USB Engine

The xSil 269B meets the Universal Serial Bus (USB) specification V2.0 and V1.1.

Support for NAND SLC / NAND MLC Flash

Widespread support for popular NAND SLC / NAND MLC flash media is available. The xSil 269B processor comes with a 4-Byte FEC Error correction algorithm that detects and corrects up to 4 Bytes in a 512 byte block. A programmable clock speed is provided to set the clock speed based on the media?s capabilities. The processor can load firmware from the NAND media itself thus obviating the need for an I2C component.

Serial port

Supports 7200 to 115.2K baud. It can be used as a debug port to communicate with V3 debugger and to load the monitor program.

General Purpose Timers

Two general-purpose timers, Timer0 and Timer1 are provided to allow firmware programmers to keep track of timeouts as well as to generate delays.

Watchdog Timer

A Watchdog Timer is provided to enable catastrophic events to interrupt the processor. The Watchdog Timer overflow causes an internal processor reset. The Processor can read the WT bit after exiting reset to determine if the WT bit is set. If it is set, a watchdog timeout occurred. The timeout is selectable to any of the following values: 2 second, 8 seconds, 16 seconds or 32 seconds.

xSil 269B Processor

The xSil 269B Processor has a built-in 16-bit processor along with a BIOS ROM. The processor operates with a specialized instruction set optimized for Mass Storage applications and USB transaction processing. The start up code for the 16-bit processor resides in a masked ROM. 

RAM Interface

 The xSil 269B chip comes with Internal RAM for data buffering. 

Masked ROM

The Masked ROM consists of the xSil 269B-processor start-up code and the functions listed below:

• Power On Initialization

• USB packet transaction management

• USB Power Management (S0..S3 modes)

• USB Enumeration Management

• API support for USB transactions, Memory Management and other functions.

• Built-in Library functions for Flash devices

The BIOS API functions are designed as Software Interrupts, making it easy for enhancements. Any Interrupt can be enhanced / modified by inserting the user defined function in the interrupt placeholder. When this interrupt is called by the BIOS, the user defined function is called first to enhance the behavior before passing it on to the standard BIOS function?s call or return without passing it on.

Programmable Read and Write cycles

The external cycles to flash using the D[15:0] bus are software configurable.