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SPI COMMUNICATION BETWEEN ST7 AND EEPROM

5.4 USE OF SEVERAL EEPROMS

It is possible to communicate with several EEPROMs. Each one is selected in turn. Then the

same protocol as described before is followed.

The main point is to reserve one I/O pin to select each device.

The selection of the devices is made using the PB2 and PB3 pins.

Figure 4. Hardware schematic for two devices

5.5 SOFTWARE

All the source files in assembly code are given in the zip file with this application note.

The source files are for guidance only. STMicroelectronics shall not be held liable for any di-

rect, indirect or consequential damages with respect to any claims arising from use of this soft-

ware.

Q

D

S

C

W

H

ST72264

110pF

M95040

1

SS(soft driven)

SCK

PB3

MISO

MOSI

Q

D

S

C

W

H

110pF

M95040

PB2