ppc460ex Applied Micro Circuits Corporation (AMCC), ppc460ex Datasheet - Page 95

• Manufacturer Part Number: ppc460ex
• Description: Powerpc 460ex Embedded Processor
• Manufacturer: Applied Micro Circuits Corporation (AMCC)

Revision 1.12 – July 17, 2008
Initialization
The PPC460EX provides the option for setting initial parameters based on default values or by reading them from
a slave PROM attached to the IIC0 bus (see “Serial EEPROM” below). Some of the default values can be altered
by strapping on external pins (see “Strapping” below).
Strapping
While the SysReset input pin is low (system reset), the state of certain I/O pins is read to enable certain default
initial conditions prior to PPC460EX start-up. The actual capture instant is the nearest reference clock edge before
the deassertion of reset. These pins must be strapped using external pull-up (logical 1) or pull-down (logical 0)
resistors to select the desired default conditions. 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 strapping options:
Serial EEPROM
During reset, initial conditions other than those obtained from the strapping pins can be read from a ROM device
connected to the IIC0 port. At the de-assertion of reset, if the Bootstrap Controller is enabled, the PPC460EX
sequentially reads 16B from the ROM device on the IIC0 port and sets the SDR0_SDSTP0:3 registers accordingly.
The initialization settings and their default values are covered in detail in the PowerPC 460EX Embedded
Processor User’s Manual User’s Manual.
AMCC Proprietary
Table 26. Strapping Pin Assignments
Preliminary Data Sheet
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 IIC Bootstrap Controller chapter in the
PPC460EX Embedded Processor User’s Manual for
details.
Serial device is enabled. The option being selected is
the IIC0 slave address that will respond with
strapping data.
Function
G (0xA8)
H (0xA4)
Option
A
B
C
D
E
F
460EX – PPC460EX Embedded Processor
(UART0CTS)
E31
0
0
0
0
1
1
1
1
Pin Strapping
(UART0DCD)
E34
0
0
1
1
0
0
1
1
(UART0DSR)
E32
0
1
0
1
0
1
0
1
95