S25FL127S View Datasheet(PDF) - Spansion Inc.
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S25FL127S Datasheet PDF : 131 Pages
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Data Sheet (Preliminary)
4.3.14
QPP or QOR Address Input Cycle
The Quad Page Program and Quad Output Read commands send address to the memory only on IO0. The
other IO signals are ignored because the device must be in Quad mode for these commands thus the Hold
and Write Protect features are not active. The host keeps RESET# high, CS# low, and drives IO0.
For QPP the next interface state following the delivery of address is the Quad Input Cycle.
For QOR the next interface state following address is a Quad Latency Cycle if there are latency cycles
needed or Quad Output Cycle if no latency is required.
4.3.15
Quad Input Cycle - Host to Memory Transfer
The Quad I/O Read command transfers four address or mode bits to the memory in each cycle. The Quad
Page Program command transfers four data bits to the memory in each cycle. The host keeps RESET# high,
CS# low, and drives the IO signals.
For Quad I/O Read the next interface state following the delivery of address and mode bits is a Quad Latency
Cycle if there are latency cycles needed or Quad Output Cycle if no latency is required. For Quad Page
Program the host returns CS# high following the delivery of data to be programmed and the interface returns
to standby state.
4.3.16
Quad Latency (Dummy) Cycle
Read commands may have zero to several latency cycles during which read data is read from the main flash
memory array before transfer to the host. The number of latency cycles are determined by the Latency Code
in the configuration register (CR[7:6]). During the latency cycles, the host keeps RESET# high, CS# low. The
host may drive the IO signals during these cycles or the host may leave the IO floating. The memory does not
use any data driven on IO during the latency cycles. The host must stop driving the IO signals on the falling
edge at the end of the last latency cycle. It is recommended that the host stop driving them during all latency
cycles so that there is sufficient time for the host drivers to turn off before the memory begins to drive at the
end of the latency cycles. This prevents driver conflict between host and memory when the signal direction
changes. The memory does not drive the IO signals during the latency cycles.
The next interface state following the last latency cycle is a Quad Output Cycle.
4.3.17
Quad Output Cycle - Memory to Host Transfer
The Quad Output Read and Quad I/O Read return data to the host four bits in each cycle. The host keeps
RESET# high, and CS# low. The memory drives data on IO0-IO3 signals during the Quad output cycles.
The next interface state continues to be Quad Output Cycle until the host returns CS# to high ending the
command.
4.4 Configuration Register Effects on the Interface
The configuration register bits 7 and 6 (CR1[7:6]) select the latency code for all read commands. The latency
code selects the number of mode bit and latency cycles for each type of instruction.
The configuration register bit 1 (CR1[1]) selects whether Quad mode is enabled to ignore HOLD# and WP#
and allow Quad Page Program, Quad Output Read, and Quad I/O Read commands.
4.5 Data Protection
Some basic protection against unintended changes to stored data are provided and controlled purely by the
hardware design. These are described below. Other software managed protection methods are discussed in
the Section, Software Interface on page 52.
4.5.1
Power-Up
When the core supply voltage is at or below the VCC (low) voltage, the device is considered to be powered off.
The device does not react to external signals, and is prevented from performing any program or erase
operation. Program and erase operations continue to be prevented during the Power-on Reset (POR)
because no command is accepted until the exit from POR to the Interface Standby state.
April 25, 2013 S25FL127S_00_02
S25FL127S
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