HD6417641 RENESAS [Renesas Technology Corp], HD6417641 Datasheet - Page 439

• Manufacturer Part Number: HD6417641
• Manufacturer: RENESAS [Renesas Technology Corp]

Tables 12.18 to 12.22 lists the minimum number of idle cycles to be inserted for the normal space
interface and the SDRAM interface. The CSnBCR Idle Setting column in the tables describes the
number of idle cycles to be set for IWW, IWRWD, IWRWS, IWRRD, and IWRRS.
Table 12.18 Minimum Number of Idle Cycles between CPU Access Cycles for the Normal
Notes:
CSnWCR.
WM Setting
1
0
1
0
1
0
1
0
1
0
0, 1
BSC Register Setting
1. Minimum number of idle cycles between the upper and lower 16-bit access cycles in the
2. Minimum number of idle cycles for other than the above cases
CSnBCR
Idle Setting
0
0
1
1
2
2
4
4
6
6
n (n>=8)
The minimum number of idle cycles is described sequentially for Iφ: Bφ (4:1/3:1/2:1/1:1).
32-bit access cycle when the bus width is 16 bits, and the minimum number of idle
cycles between continuous access cycles during 16-byte transfer
Space Interface
Read to
Read
1/1/1/2
1/1/1/2
1/1/1/2
1/1/1/2
2/2/2/2
2/2/2/2
4/4/4/4
4/4/4/4
6/6/6/6
6/6/6/6
n/n/n/n
When Access Size is Less than
Write to
Write
1/1/2/3
1/1/2/3
1/1/2/3
1/1/2/3
2/2/2/3
2/2/2/3
4/4/4/4
4/4/4/4
6/6/6/6
6/6/6/6
n/n/n/n
Bus Width
3/3/4/5
3/3/4/5
3/3/4/5
3/3/4/5
3/3/4/5
3/3/4/5
4/4/4/5
4/4/4/5
6/6/6/6
6/6/6/6
Read to
Write
n/n/n/n
Write
to Read
0/0/0/0
1/1/1/1
1/1/1/1
1/1/1/1
2/2/2/2
2/2/2/2
4/4/4/4
4/4/4/4
6/6/6/6
6/6/6/6
n/n/n/n
Contin-
uous
Read
0/0/0/0
1/1/1/1
1/1/1/1
1/1/1/1
2/2/2/2
2/2/2/2
4/4/4/4
4/4/4/4
6/6/6/6
6/6/6/6
n/n/n/n
*
1
Rev. 4.00 Sep. 14, 2005 Page 389 of 982
When Access Size Exceeds Bus Width
0/0/0/0
1/1/1/1
1/1/1/1
1/1/1/1
2/2/2/2
2/2/2/2
4/4/4/4
4/4/4/4
6/6/6/6
6/6/6/6
n/n/n/n
Contin-
uous
Write
Section 12 Bus State Controller (BSC)
*
1
Read to
Read
1/1/1/2
1/1/1/2
1/1/1/2
1/1/1/2
2/2/2/2
2/2/2/2
4/4/4/4
4/4/4/4
6/6/6/6
6/6/6/6
n/n/n/n
*
2
Write to
Write
0/0/0/1
1/1/1/1
1/1/1/1
1/1/1/1
2/2/2/2
2/2/2/2
4/4/4/4
4/4/4/4
6/6/6/6
6/6/6/6
n/n/n/n
*
REJ09B0023-0400
2
Read to
Write
3/3/4/5
3/3/4/5
3/3/4/5
3/3/4/5
3/3/4/5
3/3/4/5
4/4/4/5
4/4/4/5
6/6/6/6
6/6/6/6
n/n/n/n
*
2
Write to
Read
0/0/0/0
1/1/1/1
1/1/1/1
1/1/1/1
2/2/2/2
2/2/2/2
4/4/4/4
4/4/4/4
6/6/6/6
6/6/6/6
n/n/n/n
*
2