S29AL004D SPANSION, S29AL004D Datasheet - Page 29

• Manufacturer Part Number: S29AL004D
• Description: 4 Megabit (512 Kx 8-Bit/256 K x 16-Bit) CMOS 3.0 Volt-only Boot Sector Flash Memory
• Manufacturer: SPANSION

February 18, 2005 S29AL004D_00_A1
RY/BY#: Ready/Busy#
The RY/BY# is a dedicated, open-drain output pin that indicates whether an Em-
bedded Algorithm is in progress or complete. The RY/BY# status is valid after the
rising edge of the final WE# pulse in the command sequence. Since RY/BY# is an
open-drain output, several RY/BY# pins can be tied together in parallel with a
pull-up resistor to V
A d v a n c e
Notes:
1. VA = Valid address for programming. During a sector
2. DQ7 should be rechecked even if DQ5 = 1 because
No
erase operation, a valid address is an address within
any sector selected for erasure. During chip erase, a
valid address is any non-protected sector address.
DQ7 may change simultaneously with DQ5.
CC
.
Figure 5. Data# Polling Algorithm
Read DQ7–DQ0
Read DQ7–DQ0
I n f o r m a t i o n
DQ7 = Data?
DQ7 = Data?
Addr = VA
Addr = VA
DQ5 = 1?
START
FAIL
S29AL004D
No
Yes
No
Yes
Yes
PASS
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