BR24L□□-W Series,BR24S□□□-W Series
●Sync
data input / output timing
tR
SCL
tHD:STA
SDA
(入力)
(input)
tBUF
(出力)
(output)
SDA
tPD
tDH
tSU:DAT
tLOW
tHD:DAT
tF
tHIGH
Technical Note
SCL
tSU:STA
SDA
tHD:STA
tSU:STO
START BIT
STOP BIT
○Input
read at the rise edge of SCL
○Data
output in sync with the fall of SCL
Fig.1-(a) Sync data input / output timing
Fig.1-(b) Start-stop bit timing
SCL
SCL
SDA
DATA(1)
D1
D0
ACK
DATA(n)
ACK
�½�WR
SDA
D0
Write data
ACK
�½�W
R
Stop condition
Start condition
WP
Stop condition
ストップコンディション
(n-th
address)
tSU:WP
�½�HD:WP
Fig.1-(c) Write cycle timing
SCL
DATA(1)
SDA
D1
D0
ACK
tHIGH:WP
WP
DATA(n)
ACK
tWR
Fig.1-(d) WP timing at write execution
○At
write execution, in the area from the D0 taken clock rise of the first
DATA(1), to tWR, set WP=“LOW”.
○By
setting WP “HIGH” in the area, write can be cancelled.
When it is set WP=“HIGH” during tWR, write is forcibly ended, and data
of address under access is not guaranteed, therefore write it once again.
Fig.1-(e) WP timing at write cance
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2009.09 - Rev.D