m24m01-hr STMicroelectronics, m24m01-hr Datasheet - Page 18

• Manufacturer Part Number: m24m01-hr
• Description: 1 Mbit Serial I?c Bus Eeprom
• Manufacturer: STMicroelectronics

Device operation
3.10
18/36
Minimizing system delays by polling on ACK
During the internal Write cycle, the device disconnects itself from the bus, and writes a copy
of the data from its internal latches to the memory cells. The maximum Write time (t
shown in
can be used by the bus master.
The sequence, as shown in
●
●
●
Figure 10. Read mode sequences
1. The seven most significant bits of the device select code of a Random Read (in the 1
Current
Address
Read
Random
Address
Read
Sequential
Current
Read
Sequention
Random
Read
be identical.
Initial condition: a Write cycle is in progress.
Step 1: the bus master issues a Start condition followed by a device select code (the
first byte of the new instruction).
Step 2: if the device is busy with the internal Write cycle, no Ack will be returned and
the bus master goes back to Step 1. If the device has terminated the internal Write
cycle, it responds with an Ack, indicating that the device is ready to receive the second
part of the instruction (the first byte of this instruction having been sent during Step 1).
Table
13, but the typical time is shorter. To make use of this, a polling sequence
Dev sel *
Dev sel *
ACK
Dev sel
Dev sel
Data out N
Figure
R/W
R/W
R/W
ACK
ACK
ACK
ACK
R/W
NO ACK
9, is:
Data out 1
Byte addr
Byte addr
Data out
NO ACK
ACK
ACK
ACK
Byte addr
Byte addr
M24M01-R, M24M01-W, M24M01-HR
ACK
ACK
ACK
Data out N
Dev sel *
Dev sel *
NO ACK
R/W
st
ACK
ACK
R/W
and 4
Data out1
Data out
th
bytes) must
NO ACK
AI01105d
w
ACK
) is