BU9833GUL-W ROHM Co. Ltd., BU9833GUL-W Datasheet - Page 8

• Manufacturer Part Number: BU9833GUL-W
• Description: 256?8 Bit Electrically Erasable Prom
• Manufacturer: ROHM Co. Ltd.

○START CONDITION (RECOGNITION OF START BIT)
○STOP CONDITION (RECOGNITION OF STOP BIT)
○NOTICE ABOUT WRITE COMMAND
○DEVICE ADDRESSING
・The most significant four bits of the slave address are the “device type indentifier,”
・ The next bit (device address) identify the specified device on the bus.
・ The last bit of the stream (R/W … READ/WRITE) determines the operation to be
・All commands are proceeded by the start condition, which is a HIGH to LOW transition
・The device continuously monitors the SDA and SCL lines for the start condition and
・All communications must be terminated by a stop condition, which is a LOW to HIGH
・In the case that stop condition is not excuted in WRITE mode, transfered data will not
・Following a START condition, the master output the slave address to be accessed.
○WRITE PROTECT (WP)
○ACKNOWLEDGE
（See Fig-4 SYNCHRONOUS DATA TIMING）
（See Fig-4 SYNCHRONOUS DATA TIMING）
of SDA when SCL is HIGH.
transition of SDA when SCL is HIGH.
be written in a memory.
The device address is defined by the state of A2 input pin. This IC works
only when the device address inputted from SDA pin correspond to the state of A2 input
performed. When set to “1”, a read operation is selected ; when set to “0”, a write
operation is selected.
For this device it is fixed as “1010.”
When WP pin set to V
When WP pin set to GND(L level), enable to write 256 words (all address).
Either contorol this pin or connect to GND ( or Vcc). It is inhibited from being left
unconnected.
pin. Using this address scheme, up to two devices may be connected to the bus.
will not respond to any command until this condition has been met.
R/W set to “0” ･ ･ ･ ･ ･ ･ ･ ･ WRITE (including word address input of Random Read)
R/W set to “1” ･ ･ ･ ･ ･ ･ ･ ･ READ
１ ０ １ ０
CC
A２
(H level), write protect is set for 256 words (all address).
REV. A
０
０
Ｒ／Ｗ
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