The metabit of registers A, B, C, D is not correctly implemented.
Thes registers actually don't have one. In the TX-2, manipulation of
the metabit of these registers actually affects only the M register.
This may well be probably program-detectable, depending on whether
loading an AE register into the exchange unit (i.e. the M register)
resets the meta bit or leaves it set to the existing value. If the
latter, setging the meta bit of the A register will apparently also
set the meta bit of the B register.
Perhaps also for the modes in which the system sets the metabit of
words which were used as instruction operands.
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The metabit of registers A, B, C, D is not correctly implemented. Thes registers actually don't have one. In the TX-2, manipulation of the metabit of these registers actually affects only the M register.
This may well be probably program-detectable, depending on whether loading an AE register into the exchange unit (i.e. the M register) resets the meta bit or leaves it set to the existing value. If the latter, setging the meta bit of the A register will apparently also set the meta bit of the B register.
Perhaps also for the modes in which the system sets the metabit of words which were used as instruction operands.
Pull Request template
Please, fill in the following checklist when you submit a PR. The items you have done should be updated with a check mark (that is,
[x]instead of[ ]).cargo testpasses.cargo clippydoes not generate any warnings.cargo fmt.closes #XXXXin your commit message to auto-close the issue that your PR fixes.If any of the checklist items don't apply, please leave them un-checked.
PLEASE KEEP THE ABOVE IN YOUR PULL REQUEST.