Datasheet

Philips Semiconductors
PCF85102C-2
256 × 8-bit CMOS EEPROM with I
2
C-bus interface
Product data Rev. 04 — 22 October 2004 9 of 20
9397 750 14216
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
8.1.5 Read operations
Read operations are initiated in the same manner as write operations with the
exception that the LSB of the slave address is set to logic 1.
There are three basic read operations: current address read, random read, and
sequential read.
Remark: The lower 8 bits of the word address are incremented after each
transmission of a data byte (read or write). The MSB of the word address, which is
defined in the slave address, is not changed when the word address count overflows.
Thus, the word address overflows from 255 to 0, and from 511 to 256.
Fig 7. Master reads PCF85102C-2 slave after setting word address (write word address; read data);
sequential read.
S0ASLAVE ADDRESS WORD ADDRESS A A
SLAVE ADDRESS
acknowledge
from slave
acknowledge
from slave
acknowledge
from slave
R/W
acknowledge
from master
A
DATA
auto increment
word address
MBA703
P
no acknowledge
from master
1DATA
auto increment
word address
last byte
R/W
S1
n bytes
at this moment master
transmitter becomes
master receiver and
EEPROM slave receiver
becomes slave transmitter
Fig 8. Master reads PCF85102C-2 immediately after first byte (read mode); current address read.
S
1A
SLAVE ADDRESS DATA
A1DATA
acknowledge
from slave
acknowledge
from master
no acknowledge
from master
R/W
auto increment
word address
MBA704 - 1
auto increment
word address
n bytes last bytes
P