Boot Modes
1-26
ADSP-BF537 Blackfin Processor Hardware Reference
R/W access times; 4-cycle setup). The boot ROM evaluates the
first byte of the boot stream at address 0x2000 0000. If it is 0x40,
8-bit boot is performed. A 0x60 byte is required for 16-bit boot.
• Boot from serial SPI memory (EEPROM or flash). Eight-, 16-, or
24-bit addressable devices are supported as well as AT45DB041,
AT45DB081, and AT45DB161 data flash devices from Atmel.
The SPI uses the
PF10
output pin to select a single SPI
EEPROM/flash device, submits a read command and successive
address bytes (0x00) until a valid 8-, 16-, or 24-bit, or Atmel
addressable device is detected, and begins clocking data into the
processor.
• Boot from SPI host device – The Blackfin processor operates in SPI
slave mode and is configured to receive the bytes of the .LDR file
from an SPI host (master) agent. To hold off the host device from
transmitting while the boot ROM is busy, the Blackfin processor
asserts a flag pin to signal the host device not to send any more
bytes until the flag is deasserted. The flag is chosen by the user and
this information is transferred to the Blackfin processor via bits 8:5
of the FLAG header.
• Boot from UART – Using an autobaud handshake sequence, a
boot-stream-formatted program is downloaded by the host. The
host agent selects a baud rate within the UART’s clocking capabili-
ties. When performing the autobaud, the UART expects a “@”
(boot stream) character (eight bits data, one start bit, one stop bit,
no parity bit) on the
RXD
pin to determine the bit rate. It then
replies with an acknowledgement which is composed of 4 bytes:
0xBF, the value of
UART_DLL
, the value of
UART_DLH
, 0x00. The host
can then download the boot stream. When the processor needs to
hold off the host, it deasserts
CTS
. Therefore, the host must moni-
tor this signal.
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 ...