Disc drive READY output -- any standards?

Hi guys, Is there a defined standard as to when the READY output on a Shugart-type disc drive should go active? I'm (slowly!) working through the rebuild of one of the Amstrad drives (an EME231 I know to have working mechanical components, potentially good heads, and a fried control board), and I'm stuck on deciding how to deal with the READY output. My initial thought was to hold it inactive until a few INDEX pulses have passed, and the motor speed was within 5% of 'ideal' speed. The plan was to use a 32kHz oscillator and a 4040 counter to get a several-Hz signal, then rig up some logic to check that the disc speed was OK, and after a few valid index cycles enable the drive. Then I started wondering... am I over-engineering this? Would waiting for a couple of full disc rotations be enough to reliably generate a READY signal? Irony is that the read-amp will probably be the easiest part of the whole system... I've got a Motorola appnote which basically says "if you're using a data rate of X and a rotation speed of Y, these parameters will work" -- X and Y being the two parameters the Amstrad drive uses... That just leaves the write amp and erase logic to design (and maybe a 'write lockout' jumper). Thanks, -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/