MB86604L Datasheet, PDF (41/56 Pages) Fujitsu Component Limited. – SCSI-II Protocol Controller (with single-ended driver/receiver)

MB86604L
(8) A/N/S values in the SCSI interface timing specification
• Transfer period register (address 0Dh) and A/N values
Transfer period register
Transfer period register
A
N
A
N
Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 0 0 0 1 Prohibit Prohibit 1 0 0 0 1
9
8
00010
1
1
10010
9
9
00011
2
1
10011
10
9
00100
2
2
10100
10
10
00101
3
2
10101
11
10
00110
3
3
10110
11
11
00111
4
3
10111
12
11
01000
4
4
11000
12
12
01001
5
4
11001
13
12
01010
5
5
11010
13
13
01011
6
5
11011
14
13
01100
6
6
11100
14
14
01101
7
6
11101
15
14
01110
7
7
11110
15
15
01111
8
7
11111
16
15
10000
8
8
00000
16
16
Note: The A and N values set in the register are the assert period and the negate period respectively (unit is clock
cycles)
For the AC characteristics, A/N use numerals.
• Asynchronous setup time register (address 17h) setting and the S value.
Asynchronous setup
Asynchronous setup
time register
S
time register
S
Bit 3 Bit 2 Bit 1 Bit 0
Bit 3 Bit 2 Bit 1 Bit 0
0001
1
1001
9
0010
2
1010
10
0011
3
1011
11
0100
4
1100
12
0101
5
1101
13
0110
6
1110
14
0111
7
1111
15
1000
8
0000
16
Note: The S (setup time) value established in the set up time register during asynchronous data transfers indicates
the time from setting data in the data bus until the REQ/ACK signals are asserted.
For the AC characteristics, S uses numerals.
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