Fujitsu MAP3147FC, MAP3735FC manual Data Format, 4 Track format

Data Format

5.99 msec

Servo frame

n = 241 (zone 0) ~ 408 (zone 17)

Figure 3.4 Track format

(2)Track skew and head skew

To avoid waiting for one turn involved in head and cylinder switching, the first logical data block in each track is shifted by the number of sectors (track skew and head skew) corresponding to the switching time. Figure 3.5 shows how the data block is allocated in each track.

At the head switching location in a cylinder, the first logical data block in track t + 1 is allocated at the sector position which locates the track skew behind the sector position of the last logical data block sector in track t.

At the cylinder switching location, like the head switching location, the first logical data block in a cylinder is allocated at the sector position which locates the head skew behind the last logical sector position in the preceding cylinder. The last logical sector in the cylinder is allocated when formatting, and is an unused spare sector.

3-6 C141-E163