MD2200-DCC-V-T M-Systems Inc., MD2200-DCC-V-T Datasheet - Page 9

• Manufacturer Part Number: MD2200-DCC-V-T
• Description: Diskonchip 2000 Dip
• Manufacturer: M-Systems Inc.

3.4
NAND flash, being an imperfect memory, requires error handling. DiskOnChip 2000 implements Reed-Solomon
Error Detection Code (EDC). A hardware-generated, 6-byte error detection signature is computed each time a page
(512 bytes) is written to or read from DiskOnChip 2000.
The TrueFFS driver implements complementary Error Correction Code (ECC). Unlike error detection, which is
required on every cycle, error correction is relatively seldom required, hence implemented in software. The
combination of DiskOnChip’s built-in EDC mechanism and the TrueFFS driver ensures highly reliable error
detection and correction, while providing maximum performance.
The following detection and correction capability is provided for each 512 bytes:
3.5
The Flash Control block contains registers responsible for transferring the address, data and control information
between the DiskOnChip TrueFFS driver and the flash media. Additional registers are used to monitor the status of
the flash media (ready/busy) and of the DiskOnChip controller.
4.
DiskOnChip 2000 can operate in two modes:
Mode changes can occur due to any of the following events:
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Flash Control
Error Detection Code/Error Correction Code (EDC/ECC)
Corrects up to two 10-bit symbols, including two random bit errors.
Corrects single bursts up to 11 bits.
Detects single bursts up to 31 bits and double bursts up to 11 bits.
Detects up to 4 random bit errors.
Operating Modes
Normal mode: The device responds to every valid hardware cycle. While in this mode, all sections respond
to valid read and write cycles.
Reset mode: The device ignores all write cycles (except for the “leave Reset mode” sequence), and returns
pre-determined values for all read cycles.
A valid write sequence to the Control register
Triggering the Boot Detector circuit, which enables automatic driver loading in a PC environment.
Data Sheet, Rev. 3.7
DiskOnChip 2000 DIP Data Sheet
91-SR-002-42-8L