to load parameters from a disk formatted on another system. The degree of portability between different CP/M machines depended on the type of disk drive and controller used since many different floppy types existed in the CP/M era in both 8-inch and 5.25-inch format. Disks could be hard or soft sectored, single or double density, single or double sided, 35 track, 40 track, 77 track, or 80 track, and the sector layout, size and interleave could vary widely as well. Although translation programs could allow the user to read disk types from different machines, the drive type and controller were also factors. By 1982, soft-sector, single-sided, 40-track 5.25-inch disks had become the most popular format to distribute CP/M software on as they were used by the most common consumer-level machines of that time, such as the Apple II, TRS-80, Osborne 1, Kaypro II, and IBM PC. A translation program allowed the user to read any disks on his machine that had a similar format—for example, the Kaypro II could read TRS-80, Osborne, IBM PC, and Epson disks. Other disk types such as 80 track or hard sectored were completely impossible to read. The first half of double-sided disks (like those of the Epson QX-10) could be read because CP/M accessed disk tracks sequentially with track 0 being the first (outermost) track of side 1 and track 79 (on a 40-track disk) being the last (innermost) track of side 2. Apple II users were unable to use anything but Apple's GCR format and so had to obtain CP/M software on Apple format disks or else transfer it via serial link. The fragmented CP/M market, requiring distributors either to stock multiple formats of disks or to invest in multiformat duplication equipment, compared with the more standardized IBM PC disk formats, was a contributing factor to the rapid obsolescence of CP/M after 1981. One of the last notable CP/M-capable machines to appear was the Commodore 128 in 1985, which had a Z80 for CP/M support in addition to its native mode using a 6502-derivative CPU. Using CP/M required either a 1571 or 1581 disk drive which could read soft-sector 40-track MFM-format disks. The first computer to use a 3.5-inch floppy drive, the Sony SMC-70, ran CP/M 2.2. The Commodore 128, Bondwell-2 laptop, Micromint/Ciarcia SB-180, MSX and TRS-80 Model 4 (running Montezuma CP/M 2.2) also supported the use of CP/M with 3.5-inch floppy disks.