The reason for the games is that the cylinder number has traditionally been a half-word... Mod-"27"s went as far as possible treating it as a signed number, and Mod-"54"s to the unsigned limit.
If IBM can't move away from this archaic dependence on defining imaginary geometries of imaginary DASD, why don't they invent a new imaginary device with say 127 tracks per cylinder, 128K bytes/track? With 64K tracks, you could store almost a terabyte on one volume. sas ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
