Motorola PowerQUICC II MPC8280 Series Reference Manual page 425

} Descriptor;
Results: Source Address = 0x44332211 <MSB..LSB>
Destination Address = 0x88776655 <MSB..LSB>
Next Descriptor Address = 0x21436587 <MSB..LSB>
Byte Count = 0x67452301 <MSB..LSB>
9.13.2.2 Descriptor in Little-Endian Mode
In little endian mode, the descriptor in PCI memory should be programmed such that data
appears in descending significant byte order. If segment descriptors are written to memory
located in the PCI bus, they are obeying the rules for little endian mode.
Example: Little Endian mode descriptor's data structure. Note that the descriptor structure
must be aligned on an 8-word boundary.
struct {
double a;
double b;
double c;
double d;
} Descriptor;
Results: Source Address = 0x44332211 <MSB..LSB>
Destination Address = 0x88776655 <MSB..LSB>
Next Descriptor Address = 0x12345678 <MSB..LSB>
Byte Count = 0x76543210 <MSB..LSB>
9.14 Error Handling
The PCI bridge provides error detection and reporting. This section describes how the PCI
bridge handles different error (or interrupt) conditions.
Errors detected by the PCI bridge are reported by asserting internal error signals for each
detected error. The system error (SERR) and parity error (PERR) signals are used to report
errors on the PCI bus.
The PCI command and status registers and the error handling registers enable or disable the
reporting and detection of specific errors. There are six registers which define capture and
control functionality under error conditions. Refer to section 9.11.1.9 through section
9.11.1.14.
The PCI bridge detects illegal transfer sizes to its configuration registers, PCI master-abort
cycles, PCI received target-abort errors, PCI parity errors, and overflow/underflow errors
MOTOROLA
Freescale Semiconductor, Inc.
/* 0x8877665544332211 double word
/* 0x1122334488776655 double word
/* 0x7654321012345678 double word */
/* 0x0123456776543210 double word */
Chapter 9. PCI Bridge
For More Information On This Product,
Go to: www.freescale.com
Error Handling
*/
*/
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