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Analog Devices ADE7758
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This is a set of example captures of ADE7758 SPI communications.

Note that Chip Select is _optional_ on this device, provided that you are
careful to only use valid, full length SPI read/write requests.

Details:
http://www.analog.com/en/products/analog-to-digital-converters/integrated-special-purpose-converters/energy-metering-ics/ade7758.html


Logic analyzer setup
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The logic analyzer used was a Saleae Logic16 clone (at 50MHz):

  Probe       ADE7758 pin
  -----------------------
  0           CLK
  1           MISO
  2           MOSI
  3           IRQ


Data
----

In this case, the chip is configured to provide interrupts on voltage zero
crossings, and the host MCU is reading the status register, and then the
appropriate (phase B) voltage/current registers.

It is largely an example of SPI without CS, in SPI mode 0,1.

Correct decodings with the ADE7758 decoder should show:

  RSTATUS: 0x400
  FREQ: 0x0 (frequency is from phase A, not connected on this device)
  BVRMS: 0x10cd0c (context) or 0x10ccfa (nocontext)
  BIRMS: 0x2ac    (context) or 0x2a8    (nocontext)


ade7758-phaseB-zx-irq-context.sr
--------------------------------

Trigger with precapture on the IRQ pin falling edge.


ade7758-phaseB-zx-irq-nocontext.sr
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Trigger on SPI CLK rising edge.