Specific Blackfin Boot Modes
19-40
ADSP-BF537 Blackfin Processor Hardware Reference
shows the start of a boot sequence for an 8-bit flash/PROM
boot.
L
The processor performs an initial core byte read of location 0x0 of
the flash to determine the memory width of the flash. When boot-
ing from a FIFO in this mode, the first byte (which is part of the
first 10-byte header contained within the loader file) must be sent
twice—once for this initial core read and once for the actual boot
sequence.
16-Bit Flash/PROM Boot (BMODE = 001)
The hardware connection for this boot scenario has already been shown in
. It is one of the advantages of the 16-bit flash boot mode
that it requires the same hardware as the bypass mode. This not only
enables the user to support two booting methods on a given board by a
single jumper on the
BMODE0
pin, but it also enables programming to exe-
cute slow subroutines directly out of the flash/PROM at runtime.
A loader file for a 16-bit flash/PROM will be exactly the same as the one
shown in
, except that the ADDRESS of the 10-byte header
for the DXE count blocks will be 0xFF80 0060 or 0xFF80 0020 instead of
Figure 19-14. Timing Diagram for 8-Bit Flash Boot Sequence
AMS
all
AOE
all
ARE
all
AWE
all
A[19:1] all
D[15:0] all
0
1
0
1
0
1
0
0
1
0
0
0
0
0
0
0
0
0
0
1
1
1
00
02
02
03
04
05
06
07
08
09
0000
0012**
0000
0004
00FF
00A0
0080
0040
ADDRESS
COUNT
FLAG
READ*
*iNITIAL CORE BYTE READ FROM LOCATION
OxO OF THE FLASH TO DETERMINE 8-BIT
FLASH (0X40) OR 16-BIT FLASH (0X60).
**NOTE THAT EACH DATA READ OF AN 8-BIT
FLASH IS IN THE LEAST SIGNIFICANT BYTE
OF THE 16-BIT BUS.
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...