AN1328 STMicroelectronics, AN1328 Datasheet - Page 5

• Manufacturer Part Number: AN1328
• Description: I2C COMMUNICATION PROTOCOL WRITTEN IN FUZZYSTUDIOTM4.0 FOR ST52X430
• Manufacturer: STMicroelectronics

AN1328 - APPLICATION NOTE
Figure 6. Byte Write and Read sequences
4. HARDWARE DESCRIPTION
In Figure 7 there is a scheme that shows the simple connections between the micro ST52x430 and
ST24C04 memory. To reduce consumption, the two pull-up resistances suggest to configure the two pins
of port A as input when the memory is not in use.
Using these procedures, the user has to reserve the two pins PA0 and PA6 to allow the communication
link. Since the procedures are generalized, the user program can configure the other pins of port A ac-
cording to its preferences. The configuration will be maintained at the end of execution of each routine.
The resistance values are strictly connected with the bus capacitance, according to the graphic shown in
Figure 2. This influences also the maximum speed reachable in the serial communication. For further in-
formation about this, consult the memory datasheet.
The two chip enables are statically connected to ground. This means that, for addressing this memory
chip, we have to put the value ’0’ in bits b3 and b2 of device selector .
Figure 7. Logic Diagram
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