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neurus
Joined: 31 Mar 2004 Posts: 23 Location: Switzerland
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How can I read a 16Bit Data register with SPI_READ??? |
Posted: Fri May 21, 2004 2:06 am |
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hi
I'm triyng to read the ADC AD7705, which it has a dataregister from 16 Bits. I'm working with CCS and 18F252.
Here the code:
Code: |
long int read_adc_word()
{
long data,data1;
output_low(ADC_CS);
data1 = spi_read(data);
output_high(ADC_CS);
return data1;
}
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The comand SPI-READ return only 8Bits. I'm beginner in C, can help me anybody???
Aloha, Pablo. |
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ckielstra
Joined: 18 Mar 2004 Posts: 3680 Location: The Netherlands
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Posted: Fri May 21, 2004 2:30 am |
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Try something like:
Code: |
long int read_adc_word()
{
int8 data_low,data_high;
long data16;
output_low(ADC_CS);
data_low = spi_read(0);
data_high= spi_read(0);
output_high(ADC_CS);
data16 = make16(data_high, data_low);
return data16;
} |
I don't know the AD7705, so maybe you have to swap reading the high and low bytes. |
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neurus
Joined: 31 Mar 2004 Posts: 23 Location: Switzerland
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Posted: Fri May 21, 2004 5:21 am |
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thanks for your answer.
Aloha Pablo |
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