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6174B–ATARM–07-Nov-05
AT91FR40162S Preliminary
11. Flash Memory
The device powers on in the read mode. Command sequences are used to place the device in
other operation modes such as program and erase. The device has the capability to protect the
data in any sector (see
To increase the flexibility of the device, it contains an Erase Suspend and Program Suspend
feature. This feature will put the erase or program on hold for any amount of time and let the
user read data from or program data to any of the remaining sectors within the memory. The end
of a program or an erase cycle is detected by the READY/BUSY pin, Data Polling or by the tog-
gle bit.
The VPP pin provides data protection. When the V
PP
input is below 0.4V, the program and erase
functions are inhibited. When V
PP
is at 0.9V or above, normal program and erase operations can
be performed.
A six-byte command (Enter Single Pulse Program Mode) sequence to remove the requirement
of entering the three-byte program sequence is offered to further improve programming time.
After entering the six-byte code, only single pulses on the write control lines are required for writ-
ing into the device. This mode (Single Pulse Byte/Word Program) is exited by powering down
the device, or by pulsing the RESET pin low for a minimum of 500 ns and then bringing it back to
V
CC
. Erase, Erase Suspend/Resume and Program Suspend/Resume commands will not work
while in this mode; if entered they will result in data being programmed into the device. It is not
recommended that the six-byte code reside in the software of the final product but only exist in
external programming code.
The BYTE pin controls whether the device data I/O pins operate in the byte or word configura-
tion. If the BYTE pin is set at logic “1”, the device is in word configuration, I/O0 - I/O15 are active
and controlled by CE and OE.
If the BYTE pin is set at logic “0”, the device is in byte configuration, and only data I/O pins I/O0 -
I/O7 are active and controlled by CE and OE. The data I/O pins I/O8 - I/O14 are tri-stated, and
the I/O15 pin is used as an input for the LSB (A-1) address function.
