s-24cs16a Seiko Instruments Inc., s-24cs16a Datasheet - Page 21

• Manufacturer Part Number: s-24cs16a
• Description: 2-wire Cmos Serial E2prom
• Manufacturer: Seiko Instruments Inc.

Rev.5.1
3. Matching phases while E
The S-24CS16A does not have a pin for resetting (the internal circuit), therefore, the E
externally. If a communication interruption occurs in the E
For example, even if a reset signal is input to the microprocessor, the internal circuit of the E
long as the stop condition is not input to the E
cannot shift to the next operation. This symptom applies to the case when only the microprocessor is reset when the
power supply voltage drops. With this status, if the power supply voltage is restored, reset the E
matching the phase with the microprocessor) and input an instruction. The following shows this reset method.
[How to reset E
SDA
SCL
The E
outputting the acknowledge signal, 0 is output to the SDA line. In this status, the microprocessor cannot output an
instruction to the SDA line. In this case, terminate the acknowledge output operation or read operation, and then
input a start instruction. Figure 26 shows this procedure.
First, input the start condition.
microprocessor sets the SDA line to high level. By this operation, the E
operation or data output, so input the start condition
make doubly sure, input the stop condition to the E
*1. After 9 clocks (dummy clocks), if the SCL clock continues to be output without a start condition being input, a
Remark
_00
write operation may be started upon receipt of a stop condition. To prevent this, input a start condition after 9
clocks (dummy clocks).
2
PROM can be reset by the start and stop instructions. When the E
It is recommended to perform the above reset using dummy clocks when the system is initialized after
the power supply voltage has been raised.
condition
2
Start
PROM]
2
PROM is accessed
1
Then transmit 9 clocks (dummy clocks) of SCL.
Figure 26 Resetting E
2
Dummy clock
Seiko Instruments Inc.
2
PROM. In other words, the E
2
PROM. Normal operation is then possible.
8
*1
. When a start condition is input, the E
2
PROM, it must be reset by software.
2
9
PROM
2-WIRE CMOS SERIAL E
2
condition
PROM interrupts the acknowledge output
Start
2
PROM retains the same status and
2
PROM is reading data “0” or is
2
PROM cannot be forcibly reset
2
During this time, the
PROM is not reset as
condition
2
PROM is reset. To
Stop
S-24CS16A
2
PROM (after
2
PROM
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