FM24V01 - 128Kb I2C FRAM
Device ID
The FM24V01 device incorporates a means of
identifying the device by providing three bytes of
data, which are manufacturer, product ID, and die
revision. The Device ID is read-only. It can be
accessed as follows:
1.
2.
3.
The master sends a START command.
The master sends Reserved Slave ID 0xF8
The master sends the I
2
C-bus slave address
of the slave device it needs to identify. The
last bit is a ‘Don’t care’ value (R/W bit).
Only one device must acknowledge this byte
(the one that has the I
2
C-bus slave address).
The master sends a Re-START command.
5.
6.
The master sends Reserved Slave ID 0xF9
The Device ID Read can be done, starting
with the 12 manufacturer bits, followed by
the 9 part identification bits, and then the 3
die revision bits.
The master ends the Device ID read
sequence by NACKing the last byte, thus
resetting the slave device state machine and
allowing the master to send the STOP
command.
7.
Note: The reading of the Device ID can be stopped
anytime by sending a NACK command.
4.
Start
By Master
S
Rsvd Slave ID (F8)
Address
Start
Address
Acknowledge
No
Acknowledge
Stop
A
Slave Address
A
S
Rsvd Slave ID (F9)
A
Data Byte
A
Data Byte
A
Data Byte
1
P
By FM24V01
Acknowledge
Data
Figure 13. Read Device ID
Manufacturer ID
11
0
10
0
9
0
8
0
7
0
6
0
5
0
4
0
3
0
2
1
1
0
0
0
8
0
7
0
6
0
Product ID
5
1
4
N
3
0
2
0
1
0
0
0
Die Rev.
2
0
1
0
0
0
Ramtron
Density
Variation
Figure 14. Manufacturer and Product ID
Density: 01h=128Kb, 02h=256Kb, 03h=512Kb, 04=1Mb
Variation: Product ID bit 4 = S/N, Product ID bit 0 = reserved
The 3-byte hex code for an FM24V01 will be:
0x00 0x41 0x00
Rev. 1.1
Sept. 2011
Page 9 of 14
RAMTRON [ RAMTRON INTERNATIONAL CORPORATION ]
