Chapter 6. MPC8240 Memory Interface
6-51
FPM or EDO DRAM Interface Operation
6.3.2.2 Column Bit Multiplexing During the Column Phase (CAS)
The following list shows the relationships between the internal physical addresses
A[21
msb
–29
lsb
] and the external address pins SDMA[7:0] during the assertion of CAS:
•
In the in 32-bit bus mode, SDMA[7:0] contains A[22:29].
•
In the 64-bit bus mode, SDMA[7:0] contains A[21:28].
The encoding of SDMA[11:8] during CAS depends on the bus mode selected (32- or
64-bit) and on the number of row bits set in MCCR1 as shown in Table 6-18.
6.3.2.3 Graphical View of the Row and Column Bit Multiplexing
Figure 6-32 and Figure 6-33 provide a graphical view of the row and column bit
multiplexing.
Table 6-18. SDMA[11:8] Encodings for 32- and 64-Bit Bus Modes
Row Bits
32-Bit Bus Mode
64-Bit Bus Mode
9
A[9:11, 21]
A[8:11]
10
A[8:10, 21]
A[7:10]
11
A[7:9, 21]
A[6:9]
12
A[6:8, 21]
A[5:8]
13
A[unused, 7:8, 21]
A[unused, 6:8]
Содержание MPC8240
Страница 1: ...MPC8240UM D Rev 1 1 2001 MPC8240 Integrated Processor User s Manual ...
Страница 38: ...xviii MPC8240 Integrated Processor User s Manual TABLES Table Number Title Page Number ...
Страница 48: ...xlviii MPC8240 Integrated Processor User s Manual Acronyms and Abbreviations ...
Страница 312: ...6 94 MPC8240 Integrated Processor User s Manual ROM Flash Interface Operation ...
Страница 348: ...7 36 MPC8240 Integrated Processor User s Manual PCI Host and Agent Modes ...
Страница 372: ...8 24 MPC8240 Integrated Processor User s Manual DMA Register Descriptions ...
Страница 394: ...9 22 MPC8240 Integrated Processor User s Manual I2O Interface ...
Страница 412: ...10 18 MPC8240 Integrated Processor User s Manual Programming Guidelines ...
Страница 454: ...12 14 MPC8240 Integrated Processor User s Manual Internal Arbitration ...
Страница 466: ...13 12 MPC8240 Integrated Processor User s Manual Exception Latencies ...
Страница 516: ...16 14 Watchpoint Trigger Applications ...
Страница 538: ...B 16 MPC8240 Integrated Processor User s Manual Setting the Endian Mode of Operation ...
Страница 546: ...C 8 MPC8240 Integrated Processor User s Manual ...
Страница 640: ...INDEX Index 16 MPC8240 Integrated Processor User s Manual ...