Software routines

AN2288

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5.4

SPI interrupt routine

This routine is called just after power up of the application. This routine is used to initialize

the EEPROM if the meter is used for the first time or to get the previous accumulated kWh

and tampering information. The one pulse comparison factors and display constants are

also received from EEPROM.

Figure 19. SPI interrupt routine

SPI_IT_Routine_INIT

Is

temp!=init_EEPROM

[0]?

no

Disable SPI interrupt

Clears SPI interrupt flag

Read first byte from EEPROM

from address 0x00

temp = Read byte from EEPROM

yes

Write new values of different calibra-

tion factors and display factors

Read stored calibration fac-

tors and display factors

Set the Lite timer timebase2 for 200us

interrupt and enable interrupt, ADC on

end