HD6433682 ETC, HD6433682 Datasheet - Page 367

• Manufacturer Part Number: HD6433682
• Description: Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series
• Manufacturer: ETC

2. Random Address Read
SCL
SDA
Legend:
This is a read operation with defined read address. A random address read requires a dummy
write to set read address. The EEPROM receives a start condition, slave address + R/W code
(R/W = 0), memory address (upper) and memory address (lower) sequentially. The EEPROM
outputs acknowledgement "0" after receiving memory address (lower) then enters a current
address read with receiving a start condition again. The EEPROM outputs the read data of the
address which was defined in the dummy write operation. After receiving acknowledgement
"1" (release of a bus is allowed without receiving acknowledgement) and a following stop
condition, the EEPROM stops the random read operation and returns to a standby state.
The random address read operation is shown in figure 19.6.
condition
Start
R/ : R/
ACK: acknowledge
1
2
SDA
SCL
Slave address
3
code (0 is for a write and 1 is for a read),
4
Legend: R/ : R/
5
condition
Start
6
ACK: acknowledge
Figure 19.6 Random Address Read Operation
Figure 19.5 Current Address Read Operation
7
1
R/
8
code (0 is for a write and 1 is for a read)
ACK
9
2
Upper memory
A15
1
address
3
Slave address
A8
8
4
ACK
9
5
A7
lower memory
1
address
6
A0
8
7
ACK
9
R/
8
condition
Start
ACK
9
1
2
1
D7
Rev. 3.00, 05/03, page 337 of 472
Slave address
3
Read Data
4
5
8
D0
6
ACK
7
9
R ACK
8
conditon
Stop
9
lower memory
D7
1
address
D0
8
ACK
9
conditon
Stop