FM32L278/L276/L274/L272 - 3V I2C Companion
Start
S
No
Address
Acknowledge
Start
S
Address
By Master
Stop
Slave Address
0
A
Address MSB
A
Address LSB
Acknowledge
A
Slave Address
1
A
Data Byte
Data
1 P
By FM32L27x
Figure 16. Selective (Random) Memory Read
Address & Data
Stop
Start
S
By Master
Slave Address
0
A
Address
A
Data Byte
A
P
0 0 0
By FM32L27x
Acknowledge
Figure 17. Byte Register Write
Although not required, it is recommended that A5-A7 in the Register Address byte are zeros in order to
preserve compatibility with future devices.
Addressing F-RAM Array in the FM32L27x Family
The FM32L27x family includes 256Kb, 64Kb, 16Kb, and 4Kb memory densities. The following 2-byte address field
is shown for each density.
Table 4. Two-Byte Memory Address
Part #
1st Address Byte
2nd Address Byte
x
x
x
x
A14 A13 A12 A11 A10
A9
A9
A9
x
A8
A8
A8
A8
A7
A7
A7
A7
A6
A6
A6
A6
A5
A5
A5
A5
A4
A4
A4
A4
A3
A3
A3
A3
A2
A2
A2
A2
A1
A1
A1
A1
A0
A0
A0
A0
FM32L278
x
x
x
x
x
x
A12 A11 A10
FM32L276
FM32L274
FM32L272
x
x
x
x
A10
x
Rev. 3.0
Feb. 2009
Page 15 of 21
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