Pratik Patil

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11 years, 8 months ago.

SPI communication

Hello,

Could someone explain me clearly how I can read 24bits ADC data given by ADE7913 Analog Device? by using mbed LPC1768:

http://www.analog.com/static/imported-files/data_sheets/ADE7912_7913.pdf

Regards, Pratik

1 Answer

Wim Huiskamp
11 years, 8 months ago.

You need to set format to 8 bit mode. Then set cs low, send the read commandbyte for register 0, send three dummy bytes while reading the 24 bits of the first ADC, raise cs. Then you have to reassemble the 24 bit ADC value from the 3 received bytes. Something like this:

spi.format(8,0);

cs=0;
spi.write(0x04);
msb=spi.write(0xff);
mlsb=spi.write(0xff);
lsb=spi.write(0xff);
cs=1;
adc=(msb<<16) + (mlsb<<8) + lsb;