Revert "spi: do not shift when starting a xfer, closes #495"

whitequark · whitequark · commit cf3645713498 · 2016-07-06T05:04:38.000Z
This reverts commit 71921de. It appears to prevent the comms CPU from booting. I do not understand why.
diff --git a/artiq/gateware/spi.py b/artiq/gateware/spi.py
@@ -125,7 +125,7 @@ def __init__(self, data_width, clock_width, bits_width):
                     NextState("WAIT"),
                 )
             ).Else(
-                self.reg.shift.eq(~self.start),
+                self.reg.shift.eq(1),
                 NextState("SETUP"),
             )
         )

Original file line number	Diff line number	Diff line change
`@@ -125,7 +125,7 @@ def __init__(self, data_width, clock_width, bits_width):`
`125`	`125`	`NextState("WAIT"),`
`126`	`126`	`)`
`127`	`127`	`).Else(`
`128`		`- self.reg.shift.eq(~self.start),`
	`128`	`+ self.reg.shift.eq(1),`
`129`	`129`	`NextState("SETUP"),`
`130`	`130`	`)`
`131`	`131`	`)`