MD3331-D64-V3 M-Systems Inc., MD3331-D64-V3 Datasheet - Page 30

• Manufacturer Part Number: MD3331-D64-V3
• Description: Diskonchip Millennium Plus
• Manufacturer: M-Systems Inc.

5.1
This is the mode in which standard operations involving the flash memory are performed. Normal mode is
automatically entered when a valid write sequence is sent to the DiskOnChip Control register and Control
Confirmation register. The boot detector circuit triggers the software to set the device to Normal mode.
A write cycle occurs when both the CE# and WE# inputs are asserted. Similarly, a read cycle occurs when both the
CE# and OE# inputs are asserted. Because the flash controller generates its internal clock from these CPU cycles
and some read operations return volatile data, it is essential that the specified timing requirements contained in
Section 10.4.1 be met. It is also essential that read and write cycles are not interrupted by glitches or ringing on the
CE#, WE#, OE# address inputs. All inputs to DiskOnChip Millennium Plus are Schmidt Trigger types to improve
noise immunity.
In Normal mode, DiskOnChip Millennium Plus responds to every valid hardware cycle. When there is no activity, it
is possible to reduce the power consumption to a typical deep-power-down current of 10 µA (16/32MB) or 20 µA
(64MB) by setting the device in Deep Power-Down mode.
5.2
In Reset mode, DiskOnChip Millennium Plus ignores all write cycles, except for those to the DiskOnChip Control
register and Control Confirmation register. All register read cycles return a value of 00H. Before attempting to
perform a register read operation, the device is set to Normal mode by TrueFFS software.
5.3
In Deep Power-Down mode, DiskOnChip Millennium Plus internal high current voltage regulators are disabled to
reduce quiescent power consumption to 10 µA-20 µA typical. The following signals are also disabled in this mode:
To enter Deep Power-Down mode, a proper sequence must be written to the DiskOnChip Control registers and
DiskOnChip Control Confirmation register, and the CE# input must be negated (32/64MB devices should have CE#
input > VCC -0.2V, 16MB devices should have CE# = VCC). All other inputs should be VSS or VCC.
DiskOnChip Millennium Plus 16MB device provides an additional option to set the device into Deep Power-Down
mode. When in Normal mode, assertion of the RSTIN# signal and holding it in the low state puts the device in Deep
Power-Down mode (see dotted line in Figure 13). When the RSTIN# signal is released, the device is set in Reset
mode.
In Deep Power-Down mode, write cycles have no effect and read cycles return indeterminate data (DiskOnChip
Millennium Plus does not drive the data bus). Entering Deep Power-Down mode and then returning to the previous
mode does not affect the value of any register.
To exit Deep Power-Down mode, perform the following sequence:
DiskOnChip Millennium Plus 16MB offers an additional method to exit Deep Power-Down mode when using a
standard interface:
Applications that require both Deep Power-Down mode and boot detection require BIOS support to ensure that
DiskOnChip Millennium Plus exits from Power-Down mode prior to the expansion ROM scan. Similarly,
applications that use DiskOnChip Millennium Plus as a boot ROM must ensure that the device is not in Deep
Power-Down mode before reading the boot vector/instructions, either by pulsing RSTIN# to the asserted state and
waiting for the BUSY# output to be negated, or by entering Reset mode via software.
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Normal Mode
Deep Power-Down Mode
Reset Mode
Standard interface: input buffers A[12:0], BHE#, WE#, D[15:0] and OE# (when CE# is negated)
Multiplexed interface: input buffers AD[15:0], AVD#,WE# and OE# (when CE# is negated).
Read four times from address 1FFFH. The data returned is undefined. (For DiskOnChip Millennium 16MB
devices, this option is valid for both standard and multiplexed interface.)
Perform a single read cycle from the Programmable Boot Block with an extended access time and address
hold time as specified in Section 10.4.1. The data returned will be correct.
Data Sheet, Rev. 1.7
DiskOnChip Millennium Plus 16/32/64MByte
93-SR-002-03-8L