HP-87 and HP-9122D

[rprosperi]

If you don't specify the MSUS directly, and rely on the current 'MSI' device, then use this format:

INITIALIZE ,15,2

The leading comma provides the needed clue that the default device should be assumed.

For me, I always use the device MSUS to be really, really sure which device I'm formatting.

Is there a specific reason you are using a non-standard interleave setting?