I do not receive data from AD7707

Question

I used to work with AD7705. Now I need to configure 10 boards with AD770 test AD7707.RAR 7. I am getting wrong data from the chip. What am I doing wrong?

pifa · Answer

I connected a logic analyzer and saw how AD7707 works. Everything was fine there, the AD7707 transmitted 2 bytes of data. And I received only one byte (low), and the high one was lost. Then I took a closer look at the program and saw an error. In the previous program with AD7705 it was as follows: 
 unsigned int RD_AD7705( unsigned char channel) 
 { unsigned int data ; 
 while(RDY_AD7705); // wait DRDY=0 
 WR_AD7705(0x38 | (channel-1)); // read DATA r-r 
 ..... 
 data = SPDR; // read value in SPI data reg. (high) 
 data <<= 8;

And I did the following when copying to AD7707: 
 
 uint16_t Rd_7707(uint8_t channel) 
 { uint8_t data; - ????? 
 while(RDY_AD7707); // wait DRDY=0 
 Wr_7707(0x38 | (channel-1)); 
 ..... 
 data = SPDR; // read value in SPI data reg. (high) 
 data <<= 8; 
 
 Therefore, the high byte was lost during processing. Everything is working fine now. I will check further. 
 I plan to work with channels AIN1 (PT100) and AIN3 (0 - 10V). Here is the schematic, and also screenshots of the data transfer from the logic analyzer.

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I do not receive data from AD7707

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