S29CD016G SPANSION, S29CD016G Datasheet - Page 44

• Manufacturer Part Number: S29CD016G
• Description: 16 Megabit (512 K x 32-Bit) CMOS 2.5 Volt-only Burst Mode / Dual Boot / Simultaneous Read/Write Flash Memory
• Manufacturer: SPANSION

44
Read/Reset Command
Autoselect Command
Program Command Sequence
During the address phase, the Address Valid (ADV#) pin is asserted (taken Low)
for one clock period. Together with the edge of the CLK, the starting burst address
is loaded into the internal Burst Address Counter. The internal Burst Address
Counter can be configured to either the Linear modes (See
Configuration” on page
During the data phase, the first burst data is available after the initial access time
delay defined in the Configuration Register. For subsequent burst data, every ris-
ing (or falling) edge of the CLK triggers the output data with the burst output
delay and sequence defined in the Configuration Register.
Tables 8–9 show all the commands executed by the device. The device automat-
ically powers up in the read/reset state. It is not necessary to issue a read/reset
command after power-up or hardware reset.
After power-up or hardware reset, the device automatically enter the read state.
It is not necessary to issue the reset command after power-up or hardware reset.
Standard microprocessor cycles retrieve array data, however, after power-up,
only asynchronous accesses are permitted since the Configuration Register is at
its reset state with burst accesses disabled.
The Reset command is executed when the user needs to exit any of the other user
command sequences (such as autoselect, program, chip erase, etc.) to return to
reading array data. There is no latency between executing the Reset command
and reading array data.
The Reset command does not disable the SecSi sector if it is enabled. This func-
tion is only accomplished by issuing the SecSi Sector Exit command.
Flash memories are intended for use in applications where the local CPU alters
memory contents. As such, manufacturer and device codes must be accessible
while the device resides in the target system. PROM programmers typically ac-
cess the signature codes by raising A9 to V
onto the address lines is not generally desired system design practice.
The device contains an Autoselect Command operation to supplement traditional
PROM programming methodology. The operation is initiated by writing the Au-
toselect command sequence into the command register. The bank address (BA)
is latched during the autoselect command sequence write operation to distinguish
which bank the Autoselect command references. Reading the other bank after the
Autoselect command is written results in reading array data from the other bank
and the specified address. Following the command write, a read cycle from ad-
dress (BA)XX00h retrieves the manufacturer code of (BA)XX01h. Three
sequential read cycles at addresses (BA) XX01h, (BA) XX0Eh, and (BA) XX0Fh
read the three-byte device ID (see Table 8).
(The Autoselect Command requires the user to execute the Read/Reset command
to return the device back to reading the array contents.)
Programming is a four-bus-cycle operation. The program command sequence is
initiated by writing two unlock write cycles, followed by the program set-up com-
mand. The program address and data are written next, which in turn initiate the
Embedded Program algorithm. The system is not required to provide further con-
27).
A d v a n c e
S29CD016G
ID
. However, multiplexing high voltage
I n f o r m a t i o n
“Initial Access Delay
S29CD016_00_A4 November 5, 2004