AT49LH002-33JC Atmel, AT49LH002-33JC Datasheet - Page 9

• Manufacturer Part Number: AT49LH002-33JC
• Description: IC FLASH 2MBIT 33MHZ 32PLCC
• Manufacturer: Atmel

Specifications of AT49LH002-33JC

• Format - Memory: FLASH
• Memory Type: FLASH
• Memory Size: 2M (256K x 8)
• Speed: 33MHz
• Interface: Parallel
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: 0°C ~ 85°C
• Package / Case: 32-PLCC
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Figure 2. FWH Read Cycle
Table 4. FWH Read Cycle
Note:
3377B–FLASH–9/03
FWH4/LFRAME
Clock Cycle
FWH/LAD[3:0]
13 - 14
3 - 9
10
11
12
15
16
17
18
19
1
2
1. Field contents are valid on the rising edge of the present clock cycle.
CLK
Field Name
1101b
START
MADDR
WSYNC
RSYNC
START
MSIZE
IDSEL
TAR0
TAR1
TAR0
TAR1
DATA
DATA
1
IDSEL
IDSEL
2
A27-A24 A23-A20 A19-A16
3
0000b to 1111b
FWH/LAD[3:0]
0000b (ready)
Field Value
1111b (float)
1111b (float)
0101b (wait)
(indicates
1 byte)
1101b
0000b
1111b
1111b
YYYY
YYYY
YYYY
4
5
(1)
A15-A12
MADDR
6
Float then OUT
FWH/LAD[3:0]
OUT then float
Float then IN
A11-A8
IN then float
Direction
7
OUT
OUT
OUT
OUT
IN
IN
IN
IN
A7-A4
8
A3-A0
9
Comments
FWH4/LFRAME must be active (low) for the device to
respond. Only the last START field (before FWH4/LFRAME
transitioning high) should be recognized. The START field
contents indicate a FWH memory read cycle.
Indicates which FWH memory device should respond. If the
IDSEL field matches the strapping values on ID[3:0], then that
particular device will respond to subsequent commands.
These seven clock cycles make up the 28-bit memory
address. YYYY is one nibble of the entire address. Addresses
are transferred with the most significant nibble first.
The MSIZE field indicates how many bytes will be transferred.
The device only supports single-byte operations, so MSIZE
must be 0000b.
In this clock cycle, the master has driven the bus to all 1s and
then floats the bus prior to the next clock cycle. This is the first
part of the bus “turn-around cycle”.
The device takes control of the bus during this clock cycle.
The device outputs the value 0101b, a “wait” SYNC, for two
clock cycles. This value indicates to the master that data is not
yet available from the device. This number of wait-syncs is a
function of the device’s memory access time.
During this clock cycle, the device will generate a “ready”
SYNC indicating that the least significant nibble of the data
byte will be available during the next clock cycle.
YYYY is the least significant nibble of the data byte.
YYYY is the most significant nibble of the data byte.
The FWH memory device drives the bus to 1111b to indicate a
turn-around cycle.
The FWH memory device floats its outputs, and the master
regains control of the bus during this clock cycle.
0000b
MSIZE
10
1111b
TAR0
11
High-Z
TAR1
12
WSYNC
0101b
13
WSYNC
0101b
14
RSYNC
0000b
15
D3-D0
DATA
AT49LH002
16
D7-D4
DATA
17
1111b
TAR0
18
High-Z
TAR1
19
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