CompuServe Messages

Multi-speed

    20-May-93 09:11:34
Sb: #48721-Multi-speed
Fm: Roscoe Thomas 71777,2564
To: Bryan Shearer 72350,2234
And to think that someone could consider one disc spinning at different rates at the same time. AT the beginning of the disc the rate is fixed until the servo locks in. When the pickup is tracking the outside tracks near the end the RPM is slower. At stadard speed the data sectors are coming off the disc at 75 per second. The magic buffer size is one that contains a full disc revolution at the outer edge of the disc. Bigger doesn't seem to buy much. Double speed can reduce the time to read sectors at the outer edge as well as improve transfer rate.