Genovation, Inc.
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MiniTermPro
Appendix G: Advanced Topics
MiniTermPro Background
The Universal Serial Bus is not a robust industrial interface like RS-485 or even
RS-232. Because of this it is prone to both hardware and software errors. These
errors may be a result of ESD (static electricity) or EMI (interference cause by
machinery or other equipment) or even weak power supplies. The host PC, upon
encountering such an error, will reset and re-enumerate the entire USB bus. If
your timing is good you might even witness this by watching the PC keyboard
NumLock LED flash. In some cases even adding new hardware will trigger this
kind of event.
When the PC re-enumerates all of the USB devices, local keyboard and mouse
functions cease for a brief moment but (non-Genovation) virtual COM ports and
other connections can be orphaned completely.
MiniTermPro.exe takes care of this through four major functions:
1. It converts the incoming generic USB data into virtual COM port data.
2. Allows a physical USB port to mate with a COM port number. Without this
you might find MiniTerms showing up on different COM ports on different
days (a common problem with other USB virtual serial implementations).
3. It adds a layer of management above the host USB system that provides a
level of
fault tolerance
to the system. No matter what happens to the
USB, even if a keypad is removed and later attached again, MiniTermPro
will reestablish the connection between the PC and the 9xx keypads.
While other companies products and COM ports shut down, MiniTermPro
mends itself and allows your application to operate as if nothing
happened.
4. The icon in the system tray allows quick access to MacroMaster232
redefinition program, 9xxLoad, the download utility, the two test programs
and finally the user manual in PDF format.
