Vxworks has PT_SetMessage and PT_UndispMessage but I'm not sure how they work.
ControlViewEvent() is very similar to PT_SetMessage().
So, "Hello, world!" program for A710 (VxWorks):
private sub Initialize()
SystemEventInit()
UI_RegistDebugEventProc()
ControlViewEvent(0x18E, "Hello, world!")
Wait(1000)
ControlViewEvent(0x68, 0) ' Hide the message
end sub
Where 0x18E and 0x68 are "magic values" (camera dependent

). For a540 , for example, these values are 0x18D and 0x66 respectively.
Only one line can be displayed. Avoid of use "E18" string
