Fujitsu 80, Спецификации логического интерфейса SCSI

Страница: 59 / 310

2.2 Look-Ahead Cache Feature
C141-C010 2-9
2.2.2 Caching parameters
The IDD supports the MODE SELECT parameters (caching parameters: page code = 8) shown in Figure
2.5 for controlling the cache feature. See Section 4.1 concerning details of the MODE SELECT
parameters.
[Caching Parameters (Page Code = 8)]
Bit
Byte
7 6 5 4 3 2 1 0
0 0 0 0 0 1 0 0 0
1
X‘0A’ or X‘12’ (
Page Length
)
2 IC ABPF CAP DISC SIZE WCE MS RCD
Default 0 0 0 1 0 1 0 0
Variable 1 0 0 0 0 1 0 1
3 X‘00’ (Reserved)
4-5 Prefetch-suppressed block count
Default X‘FFFF’
Variable X‘0000’
6-7 Minimum prefetch
Default X‘0000’
Variable X‘0000’
8-9 Maximum prefetch
Default X‘00xx’
Variable X‘0000’
10-11
Maximum prefetch
limit block count
Default X‘FFFF’
Variable X‘0000’
12 FSW LBCSS DRA VS VS Reserved
Default 1 0 0 0 0 0 0 0
Variable 0 0 0 0 0 0 0 0
13 Cache segment count
Default X‘08’
Variable X‘3F’
14-15 Cache segment size
Default X‘0000’
Variable X‘0000’
16 X‘00’ (Reserved)
17-19
Non cache buffer size
Default X‘000000’
Variable X‘000000’
Remark:
The variable column indicates whether the parameter can be changed or not (if "1", the parameter
can be changed).
Figure 2.5 Cache control parameters