ADSP-2126x SHARC Processor Hardware Reference
5-17
Memory
•
B
is the base normal word address of the internal memory block; if
B
= 0x80000 (Block 0) else
B
= 0xC0000 (Block 1)
•
m
is the first 32-bit normal word address to use after the end of
48-bit words
Example: Calculating a Starting Address for 32-Bit Addresses
The last valid address is 0x82694. The number of 48-bit words (n) is:
n = 0x82694 - 0 1 = 0x2695
When you convert 0x2695 to decimal representation, the result is 9877.
The base (B) normal word address of the internal memory block is
0x80000 since the condition
0 < 10922
is TRUE.
The first 32-bit normal word address to use after the end of the 48-bit
words is given by:
m = 0 2 [(9877 MOD 21844)- TRUNC (9877 MOD 21844)/4]
m = 0 14816decimal
Convert to a hexadecimal address:
14816decimal = 0x39E0
m = 0 0x39E0 = 0x839E0
The first valid starting 32-bit address is 0x839E0. The starting address
must begin on an even address.
48-Bit Word Allocation
Another useful calculation for programs that are mixing three and four
column data is to calculate the amount of three column data that mini-
mizes the gap before starting four column data. Given the starting address
of the four column (32-bit) data, the number of 48-bit words that most
efficiently uses memory can be determined as shown in
.
Summary of Contents for ADSP-21261 SHARC
Page 30: ...Contents xxx ADSP 2126x SHARC Processor Hardware Reference ...
Page 40: ...Register Diagram Conventions xl ADSP 2126x SHARC Processor Hardware Reference ...
Page 58: ...Differences From Previous SHARCs 1 18 ADSP 2126x SHARC Processor Hardware Reference ...
Page 112: ...Secondary Processing Element PEy 2 54 ADSP 2126x SHARC Processor Hardware Reference ...
Page 178: ...Summary 3 66 ADSP 2126x SHARC Processor Hardware Reference ...
Page 204: ...DAG Instruction Summary 4 26 ADSP 2126x SHARC Processor Hardware Reference ...
Page 322: ...Setting Up DMA 7 32 ADSP 2126x SHARC Processor Hardware Reference ...
Page 436: ...SPORT Programming Examples 9 86 ADSP 2126x SHARC Processor Hardware Reference ...
Page 521: ...ADSP 2126x SHARC Processor Hardware Reference 11 31 Input Data Port rts IDP_ISR end ...
Page 522: ...Input Data Port Programming Example 11 32 ADSP 2126x SHARC Processor Hardware Reference ...
Page 590: ...Timer Programming Examples 14 20 ADSP 2126x SHARC Processor Hardware Reference ...
Page 796: ...I O Processor Registers A 174 ADSP 2126x SHARC Processor Hardware Reference ...
Page 800: ...B 4 ADSP 2126x SHARC Processor Core Manual ...
Page 846: ...Index I 36 ADSP 2126x SHARC Processor Hardware Reference ...