TC9WMB4FU Datasheet, PDF (7/17 Pages) Toshiba Semiconductor – CMOS Digital Integrated Circuits Silicon Monolithic 4096-Bit (512 × 8-Bit) 2-Wire Serial EEPROM

TC9WMB4FU
(2) Random read
A random read reads data at a specified address. A dummy write is necessary to specify an address.
In random read mode, supply a device address, R/W (= 0), and a word address after a start
condition. Unlike a byte or page write, where write data is supplied immediately, a dummy write only
specifies a word address. Then, supply a start condition and transfer a device address and R/W (= 1)
in the same way as for a current address read, to read data from the specified address.
S
W
S
T
R
T
R
S
A
I
A
E
T
R ^DEVICE T
WORD
R ^DEVICE A
O
T ADDRESS E ADDRESS (n) T ADDRESS D
P
SDA LINE
1
0
1
0
A
2
AP
10
0
WWWWWWWW
76543210
1
0
1
0
A
2
A
1
P
0
1
DDDDDDDD
76543210
M
LRAM
S
S / CS
B
BWK B
DUMMY WRITE
LA M
SC S
BK B
LA
SC
BK
DATA (n) N
O
READ
DATA (n) A
C
K
Address
increment
Figure 8
(3) Sequential read
A sequential read reads data sequentially from successive word addresses.
For either current address read or random read, upon receiving a start condition, a device address
and R/W (= 1), an acknowledge (low) is placed on the SDA line, followed by the data at the address
pointed to by the internal address counter. When an acknowledge (low) is then received, the word
address is automatically incremented so that the next data is driven out.
After the last address is reached, the word address is rolled over to address 0.
DEVICE
ADDRESS
SDA LINE
R
S
E
A
A
A
T
A
C
C
C
O
D
K
K
K
P
1
DDDDDDDD
76543210
DDDDDDDD
76543210
DDDDDDDD
76543210
DDDDDDDD
76543210
R A DATA (n)
/C
WK
READ
DATA (n)
DATA (n + 1)
READ
DATA (n + 1)
DATA (n + 2)
READ
DATA (n + 2)
DATA (n + m) N
O
READ
DATA (n + m) A
C
K
Address
increment
Address
increment
Address
increment
Address
increment
Figure 9
7
2007-10-19