MD3331-D32-V3Q18 M-Systems Inc., MD3331-D32-V3Q18 Datasheet - Page 19

• Manufacturer Part Number: MD3331-D32-V3Q18
• Description: Mobile Diskonchip Plus 128Mbits 1.8V I/o
• Manufacturer: M-Systems Inc.

3.4.2 Unique Identification (UID) Number
Each Mobile DiskOnChip Plus is assigned a 16-byte UID number. Burned onto the flash during production, the UID
cannot be altered and is unique worldwide. The UID is essential in security-related applications, and can be used to
identify end-user products in order to fight fraudulent duplication by imitators.
The UID on Mobile DiskOnChip Plus eliminates the need for an additional on-board ID device, such as a dedicated
EEPROM.
3.4.3 One-Time Programmable (OTP) Area
The 6KB OTP area is user-programmable for complete customization. The user can write to this area once, after
which it is automatically locked permanently. After it is locked, the OTP area becomes read only, just like a ROM
device.
Typically, the OTP area is used to store customer and product information such as: product ID, software version,
production data, customer ID and tracking information.
3.5
During boot, code must be executed directly from the flash media, rather than first copied to the host RAM and then
executed from there. This direct XIP code execution functionality is essential for booting.
The Programmable Boot Block with XIP functionality enables Mobile DiskOnChip Plus to act as a boot ROM
device in addition to being a flash disk. This unique design enables the user to benefit from the advantages of NOR
flash, typically used for boot and code storage, and NAND flash, typically used for data storage. No other boot
device is required on the motherboard.
Mobile DiskOnChip Plus 16MB contains a 1KB Programmable Boot Block, whereas Mobile DiskOnChip Plus
32MB contains a 2KB Programmable Boot Block. The Download Engine (DE) described in the next section
expands the functionality of this block by copying the boot code from the flash into the boot block.
When the maximum number of Mobile DiskOnChip Plus devices are cascaded, the Programmable Boot Block
provides 4KB of boot block area. The Programmable Boot Block of each device is mapped to a unique address
space.
3.6
Upon power up or when the RSTIN# signal is asserted high, the DE automatically downloads the Initial Program
Loader (IPL) from the flash to the Programmable Boot Block. The IPL is responsible for starting the boot process.
The download process is quick (1.3 ms max) and is designed so that when the CPU accesses Mobile DiskOnChip
Plus for code execution, the IPL code is already located in the Programmable Boot Block.
In addition, the DE downloads the Data Protection Structures (DPS) from the flash to the Protection State Machines
(PSMs), so that Mobile DiskOnChip Plus is secure and protected from the first moment it is active.
During the download process, Mobile DiskOnChip Plus asserts the BUSY# signal to indicate to the system that it is
not yet ready to be accessed. After BUSY# is negated, the system can access Mobile DiskOnChip Plus.
A failsafe mechanism prevents improper initialization due to a faulty VCC or invalid assertion of the RSTIN# input.
Another failsafe mechanism is designed to overcome possible NAND flash data errors. It prevents internal registers
from powering up in a state that bypasses the intended data protection. In addition, in any attempt to sabotage the
data structures causes the entire Mobile DiskOnChip Plus to become both read- and write-protected and completely
inaccessible.
19
Programmable Boot Block with eXecute In Place (XIP) Functionality
Download Engine (DE)
Data Sheet, Rev. 1.7
Mobile DiskOnChip Plus 16/32MByte 1.8V I/O
95-SR-000-10-8L