Scor­pio News

  

July–September 1988 – Volume 2. Issue 3.

Page 7 of 39

Both the winnie & controller card use standard Floppy drive power connectors for +5v & +12v, good quality cable & short runs (2 feet or less say) is the order. Do check correct polarity before connecting winnie or controller, and check good voltages & ripple after connecting them.

Three ribbon type cables are required. A 50-way cable connects the SASI port to the controller card, which should have a 220/300 ohm pack terminating near the connector. A 34-way ribbon cable using a similar layout to that of 5.25″ Floppy drives, takes control signals to the winnie (or winnie’s), the last winnie on this cable should have a termination resistor pack. A separate 20-way ribbon cable takes read/​write data to & from each winnie drive, the first drive should connect to J2 on a Xebec.

Up to 8 controller cards can run from one SASI port!! The address for your one controller should be 0, linked near the SASI connector. In addition the Xebec can store data in 256 byte or 512 byte sectors on the winnie, the link should be set to 512 for Gemini/​MAP CP/Ms;, the link is typically three pin; marked with 2 & 5.

The winnie should be set as drive 0, on Rodimes is set by a switch accessed through the side casing.

Configuring the software is the final job, for Gemini CP/M, you merely select which type of drive you’re using in the SYSTEM.CFG file and configure a new system onto a new disk (i.e. keep the old floppy system handy in case things don’t go!). For a MAP CP/M, where you are using a winnie not in the MAP data, you need to know the following winnie details:

Cylinders
This is the number of tracks on one platter surface (if the drive has 152 cylinders & 2 surfaces, it has 304 tracks).

Heads
This tells the BIOS how many surfaces are in use. (A drive with one platter has 2 surfaces, hence 2 heads.

Reduced Write Cylinder
Many drives require the write current to be reduced beyond a certain cylinder. Micro controlled ones often do this automatically, hence this may not be relevant.

Write Precompensation Cylinder
The data is written in a different‘manner beyond a certain cylinder (some times all cylinders, hence enter 0) by the Controller to improve readability.

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