Panasonic MN103001G/F01K Manual Do Utilizador

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Bus Controller (BC)
8-9
~
~
~
~
~
~
Memory control register 0B
Register symbol: MEMCTR0B
Address:
x’32000020
Purpose:
Sets the bus mode, access timing, etc., for external memory space block 0.
Bit  No.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Bit
B0
B0
B0
B0
B0
B0
B0
B0
B0
B0
B0
name
WEN4WEN3WEN2WEN1WEN0 ASN2 ASN1 ASN0 ASA1 ASA0
BM
Reset
1
1
1
0
1
0
1
1
0
1
0
0
0
0
0
0
Access
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
R
R
R/W
R
R
Bit No.
Bit name
Description
Setting conditions
2
BM
Block 0 bus mode
0: Synchronous mode (SYSCLK synchronization)
1: Asynchronous mode (MCLK synchronization)
7 to 6
ASA1 to 0
AS assert timing
00:
0MCLK
11:
3MCLK
10 to 8
ASN2 to 0
AS negate timing
000:
prohibited
Set so that:
001:
1MCLK
ASN 
 ASA
111:
7MCLK
15 to 11
WEN4 to 0
WE negate timing
Settings other than those shown below are prohibited.
Set so that:
00011:
3MCLK
WEN 
 EA
11111:
31MCLK
After the reset is released, block 0 is set as follows:
Synchronous mode
Address output end timing
3MCLK
RE negate timing
29MCLK
WE negate timing
29MCLK
RE/WE assert timing
3MCLK
Bus cycle start timing
0MCLK
Bus cycle end timing
31MCLK
AS assert timing
1MCLK
AS negate timing
3MCLK
The bus width is the bus width (8 bits or 16 bits) that accords with the mode specified by the MMOD1 and 0 pins
and the EXMOD1 and 0 pins.
Note: For details on the setting of the MMOD1 and 0 pins and the EXMOD1 and 0 pins, refer to section 8.9,
"Mode Settings."