Motorola CPCI-6115 Benutzerhandbuch

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CPCI-6115 CompactPCI Single Board Computer Installation and Use (6806800A68D)
Remote Start via the PCI Bus
Command/Response Register Description
116
   
MOTLoad uses certain areas of memory and I/O devices for its own operation. This interface 
allows the host CPU to write and read any location on the local CPU bus including those in use 
by the firmware. Host CPUs should interrogate the firmware via the memory size query 
command (as described in Opcode 0x05: Memory size Query in Appendix B of the MOTLoad 
Firmware Packager User’s Manual
) and avoid overwriting memory which is in-use by firmware; 
otherwise, erratic behavior may result.
6.3
Command/Response Register Description
The Intel 2155x SCRATCH7 register is used as the command/response register. In this register 
description, and the following command descriptions, references to the upper half of the register 
refer to bits 0 through 15, and references to the lower half of the register refer to bits 16 through 
31.
Format of command/response register (Intel 2155x SCRATCH7):
At reset, hardware clears this register. After reset, firmware writes this register with the value 
0x80525354. This value indicates that a reset event has occurred and the interface is ready to 
accept commands.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
O
W
N
Command opcode
E
R
R
Command Options
Command Data/Result 
Bit Number
Description
Bit 0
The ownership flag (OWN). A value of 1 indicates the’host’ owns the 
register. A value of 0 indicates that the local CPU owns the register.
Bits 1 to 7
7 bit command opcode field. Each command is described in more detail in 
the MOTLoad Firmware Package User’s Manual.
Bit 8
Global error status flag (ERR). If the command completed successfully, 
then this bit is written with the value 0 at command completion. If the 
command fails, it will be written with the value 1. Additional command 
specific error status may be returned in other fields of the register.
Bits 9 to 15
7 bit command option field. Each command specifies the particular 
meaning of each of the command option bits. Option bits that are unused 
are considered reserved and should be written to 0 to ensure compatibility 
with future implementations of this interface.
For most commands, bit 9 is used to specify verbose/non-verbose mode 
target command processing. In verbose mode, command related 
information is printed on the target console as the host command is 
processed. Verbose mode is selected when bit 9=0, non-verbose mode is 
set when bit 9=1.
Bits 16 to 31
16 bit data/result field. The meaning of this field is specific to each 
command opcode. Refer to the MOTLoad Firmware Package User’s 
Manual
 for error codes.