MD2200-DCC-V-T M-Systems Inc., MD2200-DCC-V-T Datasheet - Page 8

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

3.
3.1
DiskOnChip 2000 consists of the following major functional blocks, as shown in Figure 3:
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•
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3.2
The system interface block provides an easy-to-integrate SRAM-like (also EEPROM-like) interface to
DiskOnChip 2000, enabling it to interface with various CPU interfaces, such as a local bus, ISA bus, SRAM
interface, EEPROM interface or any other compatible interface.
A 13-bit wide address bus enables access to the DiskOnChip 8KB memory window (as shown in Figure 5). The
Chip Enable (CE#), Write Enable (WE#) and Output Enable (OE#) signals trigger read and write cycles. A write
cycle occurs while both the CE# and the WE# inputs are asserted. Similarly, a read cycle occurs while both the CE#
and OE# inputs are asserted. Note that DiskOnChip 2000 does not require a clock signal. The CE#, WE# and OE#
signals trigger the controller (e.g., system interface block, bus control and data pipeline) and flash access.
3.3
The boot block is responsible for answering the BIOS expansion search in PC architectures. After the BIOS
identifies DiskOnChip 2000 as a valid BIOS expansion device, it executes the code stored in the boot block. The
BIOS then loads the TrueFFS software from the flash memory into the host memory, delivering full disk capabilities
to the operating system. This code is identical for all DiskOnChip 2000 capacities, since TrueFFS automatically
detects the memory capacity of DiskOnChip 2000.
8
System Interface for host interface.
Boot Block that contains IPL ROM required for recognition during BIOS expansion search in PC architectures.
Reed-Solomon-based Error Detection and Error Correction Code (EDC/ECC) for on-the-fly error
handling.
Flash Control block that contains registers responsible for transferring the address, data and control
information between the TrueFFS driver and the flash
Theory of Operation
Overview
System Interface
Boot Block
A[0:12]
D[0:7]
CE#
WE#
OE#
Interface
Figure 3: DiskOnChip 2000 Simplified Block Diagram
System
Boot Block
(IPL ROM)
Data Sheet, Rev. 3.7
media.
EDC/ECC
Flash
Control
DiskOnChip 2000 DIP Data Sheet
Flash
91-SR-002-42-8L