Revision 2.00 – December 2, 2004
405GPr – Power PC 405GPr Embedded Processor
Data Sheet
PPC405GPr Legacy Mode Strapping Pin Assignments (Sheet 2 of 2)
Function
Option
Ball Strapping
OPB Divider from PLB 2
L25
EMCTxD1
J26
EMCTxD0
Divide by 1
Divide by 2
Divide by 3
Divide by 4
0
0
1
1
0
1
0
1
PCI Divider from PLB 2, 3
D18
GPIO1[TS1E]
C20
GPIO2[TS2E]
Divide by 1
Divide by 2
Divide by 3
Divide by 4
0
0
1
1
0
1
0
1
External Bus Divider from PLB 2
K25
EMCTxErr
K23
EMCTxEn
Divide by 2
Divide by 3
Divide by 4
Divide by 5
0
0
1
1
0
1
0
1
ROM Width
AD2
UART1_RTS/
UART1_DTR
AC2
UART1_Tx
8-bit ROM
16-bit ROM
32-bit ROM
Reserved
0
0
1
1
0
1
0
1
ROM Location
U2
HoldAck
PPC405GPr Peripheral Attach
PPC405GPr PCI Attach
0
1
PCI Asynchronous Mode Enable
Y3
ExtAck
Synchronous PCI Mode
Asynchronous Mode
0
1
PCI Arbiter Enable 3
AF18
GPIO4[TS2O]
Internal Arbiter Disabled
Internal Arbiter Enabled
0
1
Note:
1. The tune bits adjust parameters that control PLL jitter. The recommended values minimize jitter for the PLL implemented in the
PPC405GPr. These bits are shown for information only; and do not require modification except in special clocking circumstances such as
spread spectrum clocking. For details on the use of Spread Spectrum Clock Generators (SSCGs) with the PPC405GPr, visit the technical
documents area of the AMCC PowerPC web site.
2. Not all combinations of dividers produce valid operating configurations. Frequencies must be within the limits specified in “Clocking
Specifications” on page 43. Further requirements are detailed in the Clocking chapter of the PowerPC 405GPr Embedded Processor
User’s Manual.
3. Additional consideration must be given to pins that normally function as Trace signals. Improved design margin can be gained by using
three-state buffers instead of strapping resistors, and minimizing trace lengths and stubs.
52
AMCC
AMCC [ APPLIED MICRO CIRCUITS CORPORATION ]
