User`s guide

78 MPC8240 and MPC8260 Emulation
Chapter 5: Connecting and Configuring the Emulator
Configuring the Emulator
Configuration registers (MPC8260 Only)
Configuration registers are emulation probe copies of particular
registers and are used as described below. These registers may be
read/written by using the 'reg' command.
cf_immr
The cf_immr register is used by the probe to determine the location of
the internal memory map and to read/write the IMMR memory mapped
register.
Do not modify the IMMR by using a direct memory access. This will
cause the cf_immr register to be out of sync with the real IMMR
causing the emulation probe to lose track of the IMMR location.
Reading the cf_immr checks to see if the processor memory map has
moved. If the cf_immr is does not reflect the actual IMMR, then an
error is generated stating that the memory map has moved and its
location is unknown.
To recover from the condition when the cf_immr does not match the
actual IMMR, either update the cf_immr with the correct value (reg
cf_immr=xxxxxxxx) or set the cf_immr to the reset value and issue the
probe reset command (rst).
A write to the cf_immr causes a write to the real IMMR if its location is
known. Writing to the cf_immr changes the cf_immr contents and also
changes the memory mapped IMMR contents. Once again an error is
generated if the memory map has moved and cannot be located.