MCP98243 Microchip Technology Inc., MCP98243 Datasheet - Page 41

• Manufacturer Part Number: MCP98243
• Description: Memory Module Temperature Sensor W/ Eeprom For Spd
• Manufacturer: Microchip Technology Inc.

5.3.4.2
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 done by sending the word address to the
MCP98243 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 internal address pointer is
FIGURE 5-20:
© 2009 Microchip Technology Inc.
SCL
SDA
Note:
Random Read
S
In this example, ‘n’ is the current Address Word which ‘00’h and the data is the byte at address ‘n’.
1
1
SCL
2
0
SDA
Address Byte
Timing Diagram for Random Read (See Section 4.0 “Serial Communication”).
3
1
4
0
5
A
2
S
A
6
1
1
1
A
0
7
2
0
MCP98243
W
Address Byte
8
3
1
A
C
K
4
0
1
0
A
5
2
2
0
Word Address (n)
6
A
1
3
0
A
7
0
MCP98243
4
0
8
R
5
0
A
C
K
6
0
set. The master then issues the Address Byte again,
but with the R/W bit set to a ‘1’. The MCP98243 then
issues an acknowledge and transmits the 8-bit data
word. The master will not acknowledge the transfer but
does generate a stop condition and the MCP98243
discontinues transmission
1
X
7
0
2
X
MCP98243
8
0
3
Data at (n)
X
A
C
K
4
X
5
X
6
X
7
X
8
X
Master
(Figure
MCP98243
N
A
K
P
5-20).
DS22153A-page 41