spi/ade7758: examples without CS pin

[sigrok-dumps.git] / spi / ade7758 / README

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+50MHz capture of an 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.
+
+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.
+
+Two captures are provided.
+ade7758-phaseB-zx-irq-context.sr: trigger with precapture on the IRQ pin falling edge.
+ade7758-phaseB-zx-irq-nocontext.sr: trigger on spi CLK rising edge.
+
+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)
+
+Anything else has gotten the SPI decoding wrong due to the lack of chip select.