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Service_PreModeChange

Programmer's Reference Manuals
» Service Calls
» Service_PreModeChange

Service_PreModeChange

(Service &4D)
Entry
R1 77 (&4D)
R2 Mode Specifier

Case 1 – Module has no objection

Exit
R1 Preserved to pass on
R2 Preserved to pass on

Case 2 – Module objects, and takes alternative action

Exit
R1 0 (claim service)
R2 0

Case 3 – Module objects, and returns an error

Exit
R0 Pointer to error block
R1 0 (claim service)

Case 4 – Module wishes to substitute an alternative mode

Exit
R1 Preserved to pass on
R2 New Mode Specifier

Use

This service allows a module to object to a mode change, or substitute a different mode.

Notes

Service_ModeTranslation offers a better method to support new monitor types.

See also

  • Service Calls
  • Service_ModeChange
  • Service_ModeTranslation
  • Screen Modes
  • SWI Error Block
Revised on November 20, 2016 06:07:34 by Alan Robertson (52) (58.110.70.190)
Edit | Back in time (2 revisions) | See changes | History | Views: Print | Source | Linked from: Service Calls

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