24AA16/24LC16B
8.0
READ OPERATION
8.3
Sequential Read
Read operations are initiated in the same way as write
operations, with the exception that the R/W bit of the
slave address is set to ‘ 1 ’. There are three basic types
of read operations: current address read, random read
and sequential read.
Sequential reads are initiated in the same way as a
random read, except that once the 24XX16 transmits
the first data byte, the master issues an acknowledge
as opposed to a Stop condition in a random read. This
directs the 24XX16 to transmit the next sequentially-
addressed 8-bit word (Figure 8-3).
8.1
Current Address Read
To provide sequential reads, the 24XX16 contains an
The 24XX16 contains an address counter that main-
tains the address of the last word accessed, internally
incremented by ‘ 1 ’. Therefore, if the previous access
(either a read or write operation) was to address n , the
next current address read operation would access data
from address n + 1 . Upon receipt of the slave address
with R/W bit set to ‘ 1 ’, the 24XX16 issues an acknowl-
edge and transmits the 8-bit data word. The master will
not acknowledge the transfer, but does generate a Stop
condition and the 24XX16 discontinues transmission
(Figure 8-1).
internal Address Pointer that is incremented by one
upon completion of each operation. This Address
Pointer allows the entire memory contents to be serially
read during one operation.
8.4 Noise Protection
The 24XX16 employs a V CC threshold detector circuit
which disables the internal erase/write logic if the V CC
is below 1.5V at nominal conditions.
The SCL and SDA inputs have Schmitt Trigger and
filter circuits which suppress noise spikes to assure
8.2
Random Read
proper device operation, even on a noisy bus.
Random read operations allow the master to access
any memory location in a random manner. To perform
this type of read operation, the word address must first
be set. This is accomplished by sending the word
address to the 24XX16 as part of a write operation.
Once the word address is sent, the master generates a
Start condition following the acknowledge. This
terminates the write operation, but not before the inter-
nal Address Pointer is set. The master then issues the
control byte again, but with the R/W bit set to a ‘ 1 ’. The
24XX16 will then issue an acknowledge and transmit
the 8-bit data word. The master will not acknowledge
the transfer, but does generate a Stop condition and the
24XX16 will discontinue transmission (Figure 8-2).
FIGURE 8-1:
CURRENT ADDRESS READ
Bus Activity
Master
S
T
A
R
T
Control
Byte
Data (n)
S
T
O
P
SDA Line
Bus Activity
S
1 0
1
0 B2 B1 B0 1
Block
Select
Bits
A
C
K
N
o
A
C
K
P
? 2002-2012 Microchip Technology Inc.
DS21703K-page 11
相关PDF资料
24AA256-I/MS IC EEPROM 256KBIT 400KHZ 8MSOP
24AA32A/SN IC EEPROM 32KBIT 400KHZ 8SOIC
24AA32AF-I/SN IC SRL EEPROM 4KX8 1.8V 8-SOIC
24AA512-I/ST14 IC EEPROM 512KBIT 400KHZ 14TSSOP
24AA52T-I/MC IC EEPROM 2KBIT 400KHZ 8DFN
24AA64F-I/MS IC SRL EEPROM 8KX8 1.8V 8-MSOP
24AA65/P IC EEPROM 64KBIT 400KHZ 8DIP
24C00T-E/MNY IC EEPROM SER 128BIT 8TDFN
相关代理商/技术参数
24AA16-I/W16K 制造商:Microchip Technology Inc 功能描述:16K, 2K X 8 1.8V SERIAL EE WAFER - Gel-pak, waffle pack, wafer, diced wafer on film
24AA16-I/WF16K 制造商:Microchip Technology Inc 功能描述:16K, 2K X 8 1.8V SERIAL EE WA - Gel-pak, waffle pack, wafer, diced wafer on film
24AA16IP 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:16K 1.8V I 2 C O Serial EEPROM
24AA16ISL 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:16K 1.8V I 2 C O Serial EEPROM
24AA16ISN 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:16K 1.8V I 2 C O Serial EEPROM
24AA16P 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:16K 1.8V I 2 C O Serial EEPROM
24AA16SC-I/S16K 制造商:Microchip Technology Inc 功能描述:16K I2C SMARTCARD EE DIE IN WA - Gel-pak, waffle pack, wafer, diced wafer on film 制造商:Microchip Technology Inc 功能描述:16K I2C SMARTCARD EE DIE IN WAFFLE PACK, 0 DICE WPAC
24AA16SC-I/W16K 制造商:Microchip Technology Inc 功能描述:16K I2C SMARTCARD EE WAFER - Gel-pak, waffle pack, wafer, diced wafer on film