ST506

[Tony Duell]

> 
> On 4/6/07, info <info at harrells.net> wrote:
> > I need or should use a MFM drive. I know the RLL drives used a better
> > recording surface to get more data in the same size but the controller
> > is a MFM st506 from a Cromemco 250 system so it only knows MFM. I guess
> > I could use a RLL drive and low level format it but I don't remember if
> > that caused problems or not. Thanks
> 
> Formatting an RLL-certified drive with an MFM controller should not
> cause any hassles - just a loss of capacity compared to the RLL
> format.  An ST238R formats just fine as an ST225.

IIRC, every possible spacing of pulses used in MFM encoding could also 
occur in RLL encoding. So unless the drive tries to interpret the data 
stream in some way -- and AFAIK no ST412-interfaced drives do, they just 
record it on the disk -- any drive that can handle RLL encoding can also 
handle MFM encoding.

-tony