Help!Need advice on hooking up RLL drives to SH204

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rcamp48
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Help!Need advice on hooking up RLL drives to SH204

Post by rcamp48 » Wed Jan 09, 2019 9:02 pm

I have A big problem. I am trying out 3 RLL drives with the SH204 but the 3-drives will not spin up at all. I have an ST238R, an ST251 (both Seagates) and a Mitsubishi MR 535-U00 none will.spin up with power connected and the top board attached properly. Does anyone know anything about these? They are 30 years old. Russ

tzok
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Re: Help!Need advice on hooking up RLL drives to SH204

Post by tzok » Wed Jan 09, 2019 9:34 pm

With only power connected they don't spin? What drive ID is set on drive's jumpers? You need to be ID 0, while most PC disks have ID 1. Using an ST238R would be a waste, as this controller won't use RLL encoding. ST238R and ST251 are basically the same drive, but first one has a better quality surface and mechanics, making it reliable under RLL encoding. Under MFM controller like in SH204 both will have exactly same capacity (40MB).

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PaulJ
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Re: Help!Need advice on hooking up RLL drives to SH204

Post by PaulJ » Wed Jan 09, 2019 9:37 pm

As I recall in a sh204 there is an adaptec 4000 controller board which is mfm. If you want to use an rll drive you need an adaptec 4070. This is all a old memory so it maybe worth a google. I could be mistaken.. it was years ago.

tzok
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Re: Help!Need advice on hooking up RLL drives to SH204

Post by tzok » Wed Jan 09, 2019 10:46 pm

RLL drives are 100% backward compatible with RLL controllers, it is only a different encoding scheme. But better to use ST238R for repairing MegaFile 60...

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