Booting
15-32
ADSP-2126x SHARC Processor Hardware Reference
and Vi+ have built-in support for creating a boot stream com-
patible with both endian formats, and devices requiring 16-bit and 24-bit
addresses, as well as those requiring no read command at all.
Booting From an SPI Flash
For SPI flash devices, the format of the boot stream will be identical to
that used in SPI Slave mode, with the first byte of the boot stream being
the first byte of the kernel. This is because SPI flash devices do not drive
out data until they receive an 8-bit command and a 24-bit address.
Booting From an SPI PROM (16-bit address)
SPI EEPROMS only require an 8-bit opcode and a 16-bit address. These
devices begin transmitting on clock cycle 24. However, because the pro-
cessor is not expecting data until clock cycle 32, it is necessary to pad an
extra byte to the beginning of the boot stream when programming the
PROM. In other words, the first byte of the kernel will be the second byte
of the boot stream. The CrossCore and Vi+ tools automatically
handle this in the loader file generation process for SPI PROM devices.
Booting From an SPI Host Processor
Typically, host processors in SPI Slave mode transmit data on every
SPICLK
cycle. This means that the first four bytes that are sent by the host
processor are part of the first 32-bit word that is thrown away by the pro-
cessor). Therefore, it is necessary to pad an extra four bytes to the
beginning of the boot stream when programming the host, for example,
the first byte of the kernel will be the fifth byte of the boot stream. Cross-
Core and Vi+ automatically handle this in the loader file
generation process.
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 ...