AM29F040-120JC AMD (ADVANCED MICRO DEVICES), AM29F040-120JC Datasheet - Page 9

• Manufacturer Part Number: AM29F040-120JC
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Specifications of AM29F040-120JC

• Lead Free Status / Rohs Status: Not Compliant

Notes:
1. Address bits A15, A16, A17, and A18 = X = Don’t Care for all address commands except for Program Address (PA), Sector
2. Bus operations are defined in Table 1.
3. RA = Address of the memory location to be read.
4. RD = Data read from location RA during read operation.
5. Read from non-erasing sectors is allowed in the Erase Suspend mode.
Read/Reset Command
The read or reset operation is initiated by writing the
read/reset command sequence into the command reg-
ister. Microprocessor read cycles retrieve array data
from the memory. The device remains enabled for
reads until the command register contents are altered.
The device will automatically power-up in the read/
reset state. In this case, a command sequence is not
required to read data. Standard microprocessor read
cycles will retrieve array data. This default value en-
sures that no spurious alteration of the memory content
occurs during the power transition. Refer to the AC
Read Characteristics and Waveforms for the specific
timing parameters.
Autoselect Command
Flash memories are intended for use in applications
where the local CPU alters memory contents. As such,
manufacture and device codes must be accessible
while the device resides in the target system. PROM
programmers typically access the signature codes by
raising A9 to a high voltage. However, multiplexing high
voltage onto the address lines is not generally desired
system design practice.
Read/Reset
Read/Reset
Autoselect
Byte Program
Chip Erase
Sector Erase
Sector Erase Suspend
Sector Erase Resume
Address (SA), Read Address (RA), and autoselect sector protect verify.
PA = Address of the memory location to be programmed. Addresses are latched on the falling edge of the WE pulse.
SA = Address of the sector to be erased. The combination of A18, A17, A16 will uniquely select any sector (see Table 3).
PD = Data to be programmed at location PA. Data is latched on the rising edge of WE.
Read/Reset
Command
Sequence
Cycles
Req’d
Write
Bus
1
4
4
4
6
6
Erase can be suspended during sector erase with Addr (don’t care), Data (B0H)
Erase can be resumed after suspend with Addr (don’t care), Data (30H)
XXXXH
5555H
5555H
5555H
5555H
5555H
Write Cycle
Addr
First Bus
Table 4. Am29F040 Command Definitions
Data
AAH 2AAAH 55H
AAH 2AAAH 55H
AAH 2AAAH 55H
AAH 2AAAH 55H
AAH 2AAAH 55H
F0H
Second Bus
Addr
Write Cycle
Data
Am29F040
5555H
5555H
5555H A0H
5555H
5555H
Addr
Write Cycle
Third Bus
The device contains a command autoselect operation
to supplement traditional PROM programming method-
ology. The operation is initiated by writing the auto-
select command sequence into the command register.
Following the command write, a read cycle from ad-
dress XX00H retrieves the manufacture code of 01H. A
read cycle from address XX01H returns the device
code A4H (see Table 2). All manufacturer and device
codes will exhibit odd parity with the MSB (DQ7)
defined as the parity bit.
Scanning the sector addresses (A16, A17, A18) while
(A6, A1, A0) = (0, 1, 0) will produce a logical “1” at
device output DQ0 for a protected sector.
To terminate the operation, it is necessary to write the
read/reset command sequence into the register.
Byte Programming
The device is programmed on a byte-by-byte basis.
Programming is a four bus cycle operation. There are
two “unlock” write cycles. These are followed by the
program setup command and data write cycles. Ad-
dresses are latched on the falling edge of CE or WE,
whichever happens later and the data is latched on the
rising edge of CE or WE, whichever happens first. The
Data
F0H
90H
80H
80H
5555H
5555H
Addr
00H
01H
Fourth Bus
Read/Write
RA
PA
Cycle
Data
A4H
AAH
AAH
01H
RD
PD
2AAAH 55H
2AAAH 55H
Write Cycle
Addr
Fifth Bus
Data
5555H
Write Cycle
Addr
Sixth Bus
SA
Data
10H
30H
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