November 2020 release

Overview

This version is needed for Boost module version 0B. It contains some corrections to secondary functions and an update to the API.

API 1

Implements API version 1 with several new entry points, see the API document for more information.

Corrections

• Secondary functions without any semi-merged argument would not
  display properly in program mode. It could go and display DATA ERROR
  or do weird things rather than showing the instruction.

• Running secondary functions from program memory that did not have
  any semi-merged argument caused the execution of the instruction
  byte inside the text wrapper, which was the function number. This
  could cause all kinds of problems, but as they usually are low
  numbered it was often a LBL. If the secondary function was a test
  function that may skip the next line, it would not work as intended.

• Secondary functions using default semi-merged operand did not work
  properly and ended up giving NONEXISTENT error.

Bugfix release

Corrections

• Loading OS4 by itself without Boost present caused the HP-41 not being able to turn on properly.
• The ensureHPIL routine would most likely report "NO HP-IL" even when there was an HP-IL module present.
• Secondary functions could not be execute if a printer was attached.

Initial release

This release is needed by the Ladybug module version 1A.

If you are a developer, refer to the supplied documentation for how to develop with OS4.