The only problem is: My 17 inch MacBookPro has Thunderbolt, Fire wire 800, ethernet and USB 2.0; no 9 pin serial port. I'll need to get an adapter.
That's why I
linked to
them. Note that the default theme for this forum makes it hard to see the color of links sometimes. I bolded the links in this post.
I'd recommend just going ahead and doing the µSD thing. The serial cable is useful as a diagnostic, but you can always just try the fix (µSD) and if that works, it's as good a diagnosis as any.
I want the serial cable and the experience for diagnostic purposes in the future. I need to get me an adapter from Thunderbolt 1 to 9 Pin serial. Then 9 Pin serial to ethernet to go into the serial port of the SP20.