Hi Chris, The DRDY pulse is falling edge pulse is very consistent with respect to each other and happens at the same interval. However the rising edge varies much more with its timing see image below. By changing the direction of which the scope triggers on, with respect to the falling edge the the edge falls at very specific interval. Conversely triggering off the falling edge causes jitters both before and after the data ready pulses. In addition to this the width of the pulse can vary by as much as 50 useconds. Does the data from the ADS1282 ever change or re sample during the duration of the data ready pulse? We are under the impression as soon as the data ready line falls it stores a sample and keeps it for the duration? Another observation we have is this: In the datasheet, once we have issued read data continuous we should get data ready every 250us (assuming 4khz sample rate). then we need to trigger SPI transaction to read on the falling edge.The figure 56 in 9.26 shows 4 bytes of data read. But what we seen with the part is that we need to read 5 bytes and discard the first byte. i.e we initiate 5 byte reads, B0, B1, B2, B3, B4, discard B0 keep B1,B2,B3,B4 with B1 as MSB and B4 as LSB. Is 5 Byte read correct or is this the source of our jitter issues?
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