System Debug Reference Manual (32650-90888)

238 Chapter6
System Debug Command Specifications M-X
MR
newvalue The new value for the register can optionally be supplied on the command
line. If the new value was omitted, Debug displays the old value, and
prompts for the new value. To retain the original value, just hit return.
When a register is modified, the actual machine registers are not changed
until the process is resumed. That is, the new value is recorded and takes
effect when Debug is exited using the CONTINUE or EXIT commands.
Furthermore the value is applied only to the PIN being debugged. This is
true of all but several special registers that are expected to remain
constant during the life of MPE XL. The list of these registers follows:
sR6
sR7
tr0-tr7 Alias for cr24 - cr31
cCr Alias for cr10
iVa Alias for cr14
eIem Alias for cr15
eIrr Alias for cr23
When one of these registers is modified, the new value takes effect
immediately . Since these registers are global across all processes, all
other users are affected by the change.
FP6 FARG2 dm FP argument register 2
FP7 FARG3 dm FP argument register 3
FP8 none dm FP register 8
[vellip]
FP15 none dm FP register 15
FPSTATUS none dm FP status reg (left half of FP0)
FPE1 none dm FP exception reg 1 (right half of FP0)
FPE2 none dm FP exception reg 2 (left half of FP1)
FPE3 none dm FP exception reg 3 (right half of FP1)
FPE4 none dm FP exception reg 4 (left half of FP2)
FPE5 none dm FP exception reg 5 (right half of FP2)
FPE6 none dm FP exception reg 6 (left half of FP3)
FPE7 none dm FP exception reg 7 (right half of FP3)
Table 6-5. Floating Point Registers
Name Alias Access Description