s-24c04bphal Seiko Instruments Inc., s-24c04bphal Datasheet - Page 16

• Manufacturer Part Number: s-24c04bphal
• Description: 2-wire Cmos Serial E2prom
• Manufacturer: Seiko Instruments Inc.

7.2 Random read
16
2-WIRE CMOS SERIAL E
S-24C04BPHAL
Random read is a mode used when data is read from arbitrary memory addresses.
To load a memory address into the address counter inside the E
following the procedure below.
When the E
start condition signal, it outputs the acknowledge signal.
Next, the E
address has now been loaded into the address counter of the E
Following this, the E
not performed during dummy write.
The memory address is loaded into the memory address counter inside the E
After that, the master device can read the data starting from the arbitrary memory address by transmitting a
new start condition signal and performing the same operation as that in the “Current Address Read”.
That is, when the E
following the start condition signal, it outputs the acknowledge signal.
Next, 8-bit data is output from the E
not output an acknowledge signal and transmits the stop condition signal instead. Reading is then complete.
SDA
line
S
T
A
R
T
M
S
B
1 0 1 0
2
2
PROM receives a 7-bit device address and the 1-bit read/write instruction code “0” following the
PROM receives an 8-bit word address and outputs the acknowledge signal. The memory
ADDRESS
DEVICE
X X P0
2
2
PROM receives the write data during byte or page writing. However, data reception is
PROM receives a 7-bit device address and the 1-bit read/write instruction code “1”
DUMMY WRITE
S
B
L
W
W
R
R
E
T
0
/
I
2
A
C
K
PROM
W7 W6 W5 W4 W3 W2 W1 W0
WORD ADDRESS (n)
2
PROM in synchronization with the SCL clock. The master device does
Figure 14 Random Read
Seiko Instruments Inc.
C
A
K
R
S
T
A
T
M
S
B
1 0 1 0
ADDRESS
DEVICE
2
PROM.
X X P0
2
PROM, first perform a dummy write
L
S
B
W
R
R
E
A
D
1
/
C
A
K
D7 D6 D5 D4 D3 D2 D1 D0
2
PROM during dummy write.
No ACK from
master device
DATA
ADR INC
Rev.3.0
S
T
O
P
_00