PPC460EX-SUB800N AMCC, PPC460EX-SUB800N Datasheet - Page 102

• Manufacturer Part Number: PPC460EX-SUB800N
• Manufacturer: AMCC

460EX – PPC460EX Embedded Processor
Boot Configuration
The PPC460EX supports several configurable boot parameters that must be initialized prior to booting. These
parameters are configured by one of several default boot options or programmed by data read from an IIC serial
EEPROM (see “Serial EEPROM” below). Strap signals sampled during reset select which method is used to
initialize the boot parameters (see “Strapping” below).
Strapping
The Bootstrap Controller selects the boot options based on the state of the strap signals during reset. The strap
signals are sampled on the rising edge of SysClk while SysReset is driven low. They must not change state until
after SysReset is driven high in order to guarantee the correct boot option is selected.
These pins are used for strap functions only during reset. Following reset, they are used for normal functions. The
signal names assigned to the pins for normal operation are shown in parentheses following the pin number.
The following table lists the strapping pins along with their functions and boot strap options:
Serial EEPROM
Boot Options G and H enable the Bootstrap Controller to read 16 bytes of configuration data from a serial
EEPROM attached to the IIC0 bus after SysReset deasserts. The Bootstrap Controller stores the data in the
SDR0_SDSTP0:3 registers.
Note: The IIC serial EEPROM must have a one-byte base address. Multi-byte base addresses are not supported.
The initialization settings and their default values are covered in detail in the PowerPC 460EX/EXr/GT Embedded
Processor User’s Manual User’s Manual.
102
Table 36. Strapping Pin Assignments
Serial device is disabled. Each of the six options (A–
F) is a combination of boot source, boot-source
width, and clock frequency specifications. Refer to
the PPC460EX Embedded Processor User’s Manual
for details.
Serial device is enabled. Boot Option G and H
enable the Bootstrap Controller to program boot
parameters using data read from an IIC serial
EEPROM. Option G and H support different IIC
addresses.
Function
Boot Option
G (0xA8)
H (0xA4)
A
B
C
D
E
F
(UART0CTS)
E31
0
0
0
0
1
1
1
1
Preliminary Data Sheet
Revision 1.19 – June 17, 2009
Strapping Pins
(UART0DCD)
E34
0
0
1
1
0
0
1
1
AMCC Proprietary
(UART0DSR)
E32
0
1
0
1
0
1
0
1