M58BF008
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Program (PG).
The Program instruction consists
of two write cycles, the first is the program set-up
command 40h at the address 00000h. This is fol-
lowed by a second write cycle to latch the address
and data to be programmed. This second com-
mand starts the P/E.C. A program operation can
be aborted by writing FFFFFFFFh to any address
after the program set-up command has been giv-
en. While programming is in progress only the
Read Status Register and Program Suspend in-
structions are valid.
Read operations output the Status Register after
the program operation has started. The Status
Register bit 7 is ’0’ while programming is in
progress and is set to ’1’when it is completed. Af-
ter completion the Status Register bit 4 is set to’1’
if there has been a programmingfailure.
Programming should not be attempted when the
V
PP
Program/Erase Supply Voltage is out of the
range V
PP1
or V
PPH
as the results will be uncer-
tain. The Status Register bit 3 is set to ’1’if V
PP
is
not within the allowed ranges when programming
is attempted or if it falls out of the ranges during
program execution.
The program operation aborts if V
PP
drops out of
the allowed ranges or if Reset/Power-Down RP
falls to V
IL
. As data integrity cannot beguaranteed
when the program operation is aborted, the mem-
ory block must be erased and programming re-
peated.
A Clear Status Register instruction must be given
to clear the Status Register bits.
Overlay Block Program (OBPG).
The
Block Programinstruction consists of two write cy-
cles, the first is the program set-up command 04h
at the address 00000h. This is followed by a sec-
ond write cycle to latch theaddress and data to be
programmed. This second command starts the P/
E.C.
The operation is executed as described for the
Program (PG) instruction of the Main memory ar-
ray.
While programming of the Overlay block in
progress onlythe ReadStatus Register instruction
is valid.
Program/Erase Suspend (PES).
As
erasure takes of the order of seconds to complete
and programming a few microseconds, a Pro-
gram/Erase Suspend instruction is implemented.
Program/Erase Suspend interrupts the operations
to allow reading or programming in a block other
than one in which program or erase is suspended.
A Program/Erase Suspend instruction is accepted
only during a Program or Erase instruction. When
the Program/Erase Suspend command is written
to the Command Interface, the P/E.C. freezes the
Overlay
memory
program or erase operation. The suspended pro-
gram oreraseoperation maybe restartedby using
the Program/Erase Resume instruction. Program/
Erase Suspend is not allowed during the Overlay
block program/erase operation and the command
is ignored.
The Program/Erase Suspend instruction consists
of one write cycle giving the command B0h at the
address 00000h.
If a program operation is in progress when the in-
struction is given, the Status Register bits 4 and 6
are set to ’1’ after it has been suspended. If an
erase operation is in progress when theinstruction
is given, the Status Register bits 5 and 6 are set to
’1’after it has been suspended.
The valid instructions that may be given to the
memory while programing is suspended are
– Read Memory Array (RD)
– Read Status Register (RSR)
– Read Electronic Signature (RSIG)
– Program/Erase Resume (PER)
In addition, while erasure is suspended, the Pro-
gram (PG) instruction may be given.
In Program/Erase Suspendmode the memory can
be placed in a pseudo-standby mode by taking
Chip Enable /E to VIH to reduce power consump-
tion.
Program/Erase Resume (PER).
If a Program/
Erase Suspend instruction has previously been
executed, then the operation may be resumed by
giving the command D0h at the address 00000h.
The Status Register bits 4, 5 and 6 are cleared
when program or erase resumes. A Read Memory
Array instruction will output theStatus Register af-
ter program or erase is resumed.
Suggested flow charts for software that uses pro-
gramming, erasure and program/erase suspend/
resume operations are shown in Figures 11, 12,
13 and 14.
Asynchronous/Synchronous Read Toggle(ART)
.
Asynchronous Read Memory Array is thememory
default at power-up or when returning from Power-
Down. To read data in Synchronous mode, either
single or burst, the Asynchronous/Synchronous
Read Toggle instruction must be used.
The Asynchronous/Synchronous Read Toggle in-
struction consists of one write cycle giving the
command 60h at the address 00000h. Two con-
secutive instructions are not recognised and an-
other Instruction, for example the Read Memory
Array, must be given before another Asynchro-
nous/Synchronous Read Toggle will be recogn-
ised.