Chapter 7 External Bus Controller
7-5
7.3.3 Address
Mapping
Each of the eight channels can use the Base Address field (EBBAR.BA[31:20]) and the Channel Size
field (EBCCRn.CS[3:0]) of the External Bus Channel Control Register to map to any physical address.
A channel is selected when the following equation becomes True.
paddr[31:20] & !Mask[31:20] == BA[31:20] & !Mask[31:20]
In the above equation, paddr represents the accessed physical address, Mask[31:20] represents the
address mask value selected from Table 7.3.1 from the Channel Size, the ampersand (&) represents the
AND operation, and the exclamation mark (!) represents the Logical NOT for each bit.
Operation is indeterminate when either multiple channels are selected simultaneously, or a channel is
selected simultaneously with the SDRAM Controller or PCI Controller.
Table 7.3.2 Address Mask
CS[3:0]
Channel Size
Address Mask[31:20]
0000 1
MB 0000_0000_0000
0001 2
MB 0000_0000_0001
0010 4
MB 0000_0000_0011
0011 8
MB 0000_0000_0111
0100 16
MB 0000_0000_1111
0101 32
MB 0000_0001_1111
0110 64
MB 0000_0011_1111
0111 128
MB 0000_0111_1111
1000 256
MB 0000_1111_1111
1001 512
MB 0001_1111_1111
1010 1
GB 0011_1111_1111
1011 Reserved
Reserved
1100 Reserved
Reserved
1101 Reserved
Reserved
1110 Reserved
Reserved
1111 Reserved
Reserved
Summary of Contents for TMPR4925
Page 1: ...64 Bit TX System RISC TX49 Family TMPR4925 Rev 3 0 ...
Page 4: ......
Page 15: ...Handling Precautions ...
Page 16: ......
Page 18: ...1 Using Toshiba Semiconductors Safely 1 2 ...
Page 40: ...3 General Safety Precautions and Usage Considerations 3 18 ...
Page 42: ...4 Precautions and Usage Considerations 4 2 ...
Page 43: ...TMPR4925 ...
Page 44: ......
Page 54: ...Chapter 1 Features 1 8 ...
Page 58: ...Chapter 2 Block Diagram 2 4 ...
Page 88: ...Chapter 4 Address Mapping 4 12 ...
Page 226: ...Chapter 8 DMA Controller 8 58 ...
Page 260: ...Chapter 9 SDRAM Controller 9 34 ...
Page 480: ...Chapter 15 Interrupt Controller 15 32 ...
Page 554: ...Chapter 19 Real Time Clock RTC 19 8 ...
Page 555: ...Chapter 20 Removed 20 1 20 Removed ...
Page 556: ...Chapter 20 Removed 20 2 ...
Page 564: ...Chapter 21 Extended EJTAG Interface 21 8 ...
Page 580: ...Chapter 22 Electrical Characteristics 22 16 ...
Page 588: ...Chapter 24 Usage Notes 24 2 ...