s29ns01gr Meet Spansion Inc., s29ns01gr Datasheet - Page 42

• Manufacturer Part Number: s29ns01gr
• Description: S29ns01gr 1gb 64 M X 16 Bit , 1.8 V Burst Simultaneous Read/write, Multiplexed Mirrorbit Flash Memory
• Manufacturer: Meet Spansion Inc.

7.9
7.10
7.11
42
Handshaking
Hardware Reset
Software Reset
The handshaking feature allows the host system to detect when data is ready to be read by simply monitoring
the RDY (Ready) pin, which is a dedicated output controlled by CE#. The NS01GR has an option for two CE#
pins. Other devices (512/256/128) have only one CE# pin.
When CE# input is Low, the RDY output signal is actively driven. When both of the CE# inputs are High the
RDY output is high-impedance. When CE# input and OE# input is Low, the A/DQ15-A/DQ0 output signals are
actively driven. When both of the CE# inputs are High, or the OE# input is High, the A/DQ15-A/DQ0 outputs
are high-impedance.
When the device is operated in synchronous mode, and OE# is low (active), the initial word of burst data
becomes available after the rising edge of the RDY. CR.8 in the Configuration Register allows the host to
specify whether RDY is active at the same time that data is ready, or one cycle before data is ready (see
Table 7.12 on page
When the device is operated in asynchronous mode, RDY will be high when CE# is low (active).
The RESET# input provides a hardware method of resetting the device to idle state. When RESET# is driven
low for at least a period of t
outputs, resets the configuration register, and ignores all read/write commands for the duration of the reset
operation. The device also resets the internal state machine to idle state.
To ensure data integrity, the operation that was interrupted should be reinitiated once the device is ready to
accept another command sequence.
When RESET# is held at V
not at V
See
Software reset is part of the command set (see
state and must be used for the following conditions:
Reset commands are ignored once programming/erasure has begun until the operation is complete.
Software Functions and Sample Code
Note:
Base = Base Address.
The following is a C source code example of using the reset function. Refer to the Spansion Low Level Driver
User’s Guide (available on www.spansion.com) for general information on Spansion Flash memory software
development guidelines.
/* Example: Reset (software reset of Flash state machine) */
1. Exit ID/CFI mode
2. Exit Secure Silicon Region mode
3. Exit Configuration Register mode
4. Exit SSR Lock mode
Figure 10.10
*( (UINT16 *)base_addr + 0x000 ) = 0x00F0;
SS
, the standby current is greater.
Reset Command
Cycle
for timing diagrams
30).
D a t a
RP
SS
S29NS-R MirrorBit
, the device immediately terminates any operation in progress, tristates all
, the device draws CMOS standby current (I
S h e e t
Operation
Write
Table 7.29 Reset
( A d v a n c e
®
Table 11.1 on page
Flash Family
Byte Address
Base + xxxh
I n f o r m a t i o n )
60) that also returns the device to idle
CC4
Word Address
). If RESET# is held at V
Base + xxxh
S29NS-R_00_03 May 9, 2008
00F0h
Data
IL
, but