SDRAM Controller (SDC)
18-68
ADSP-BF535 Blackfin Processor Hardware Reference
During read transfers to SDRAM banks, reads are always done of all bytes
in the bank regardless of the transfer size. This means for 32-bit SDRAM
banks,
SDQM[3:0]
are all zeros and for 16-bit SDRAM banks,
SDQM[1:0]
are zeros,
SDQM[2]
is 1, and
SDQM[3]
outputs
IA[1]
.
The only time that the
SDQM[3:0]
pins are high is when bytes are masked
during write transfers to the SDRAM banks. At all other times, the
SDQM[3:0]
pins are held low (with the exception of
SDQM[3]
when the
SDRAM banks are 16-bit wide). This means for 32-bit SDRAM banks,
SDQM[3:0]
are all zeros, and for 16-bit SDRAM banks
SDQM[1:0]
are zeros,
SDQM[2]
is 1, and
SDQM[3]
outputs
IA[1].
The pin configurations in
Table 18-16
are internally set up and not
programmable.
Содержание ADSP-BF535 Blackfin
Страница 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Страница 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 908: ...SDRAM Controller External Bus Interface Unit B 36 ADSP BF535 Blackfin Processor Hardware Reference...