CD016G0PFA Advanced Micro Devices, Inc., CD016G0PFA Datasheet - Page 52

• Manufacturer Part Number: CD016G0PFA
• Description: 16 Megabit(512 K X 32-Bit),CMOS 2.5 Volt-only Burst Mode, Dual Boot, Simultaneous Read/write Flash Memory
• Manufacturer: Advanced Micro Devices, Inc.

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Sector Erase and Program Suspend Operation Mechanics
The Sector Erase and Program Suspend command is ignored if written during the
execution of the Chip Erase operation or Embedded Program Algorithm (but will
reset the chip if written improperly during the command sequences). Writing the
Sector Erase and Program command during the Sector Erase time-out results in
immediate termination of the time-out period and suspension of the erase oper-
ation. Once in Erase Suspend, the device is available for reading (note that in the
Erase Suspend mode, the Reset command is not required for read operations and
is ignored) or program operations in sectors not being erased. Any other com-
mand written during the Erase Suspend mode is ignored, except for the Sector
Erase and Program Resume command. Writing the Erase and Program Resume
command resumes the sector erase operation. The bank address of the erase
suspended bank is required when writing this command
If the Sector Erase and Program Suspend command is written during a program-
ming operation, the device suspends programming operations and allows only
read operations in sectors not selected for programming. Further nesting of either
erase or programming operations is not permitted. Table 18 summarizes permis-
sible operations during Erase and Program Suspend. (A busy sector is one that is
selected for programming or erasure.):
When the Sector Erase and Program Suspend command is written during a Sector
Erase operation, the chip will take between 0.1 µs and 20 µs to actually suspend
the operation and go into the erase suspended read mode (pseudo-read mode),
at which time the user can read or program from a sector that is not erase sus-
pended. Reading data in this mode is the same as reading from the standard read
mode, except that the data must be read from sectors that have not been erase
suspended.
Polling DQ6 on two immediately consecutive reads from a given address provides
the system with the ability to determine if the device is in Erase or Program Sus-
pend. Before the device enters Erase or Program Suspend, the DQ6 pin toggles
between two immediately consecutive reads from the same address. After the
device has entered Erase suspend, DQ6 stops toggling between two immediately
consecutive reads to the same address. During the Sector Erase operation and
also in Erase suspend mode, two immediately consecutive readings from the
erase-suspended sector causes DQ2 to toggle. DQ2 does not toggle if reading
A successful erase pulse has a duration or 1.2 ms
number of previous erase cycles (among other factors).
A successful sector erase operation requires 300 successful erase pulses.
An internal counter monitors the number of erase pulses initiated and has a
maximum value of 5980. The counter is incremented by one every time an
erase pulse is initiated, regardless of whether or not that erase pulse is suc-
cessful. An erase pulse is terminated immediately when the suspend com-
mand is executed. A new erase pulse is initiated when the resume command
is executed (and the counter is incremented).
Given that 300 successful erase pulses are required, a successful sector erase
operation shall have a maximum of 5680 erase suspends.
Table 18. Allowed Operations During Erase/Program Suspend
Busy Sector
Non-busy
Sector
sectors
A d v a n c e
Program Suspend
Program Resume
Read Only
S29CD016G
I n f o r m a t i o n
Read or Program
Erase Suspend
Erase Resume
±
20%, depending on the
S29CD016_00A0 March 22, 2004