at88sc153 ATMEL Corporation, at88sc153 Datasheet - Page 15

• Manufacturer Part Number: at88sc153
• Description: 3 X 64 X 8 Secure Memory With Authentication
• Manufacturer: ATMEL Corporation

10. Device Operation
10.1
10.2
10.3
10.4
10.5
10.6
10.7
1016E–SMEM–12/07
Clock and Data Transitions
Start Condition
Stop Condition
Acknowledge
Standby Mode
Acknowledge Polling
Device Timing
The SDA pin is normally pulled high with an external device. Data on the SDA pin may change
only during SCL-low time periods
periods will indicate a start or stop condition as defined below.
A high-to-low transition of SDA with SCL high is a start condition that must precede any other
command
A low-to-high transition of SDA with SCL high is a stop condition. After a read sequence, the
stop command will place the device in a standby power mode
All addresses and data are serially transmitted to and from the device in 8-bit words. The device
sends a “0” to acknowledge that it has received each byte. This happens during the ninth clock
cycle.
The AT88SC153 features a low-power standby mode that is enabled upon power-up and after
the receipt of the stop bit and the completion of any internal operations.
Once the internally-timed write cycle has started and the device inputs are disabled, acknowl-
edge polling can be initiated. This involves sending a start condition followed by the command
byte representative of the operation desired. Only if the internal write cycle has completed will
the device respond with a “0”, allowing the sequence to continue.
Figure 10-1. Start and Stop Definition
(Figure 10-1 on page
15).
(Figure 10-2 on page
16). Data changes during SCL-high time
(Figure 10-1 on page
15).
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