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VDUXV
Programmer's Reference Manuals
» Part 1 - Introduction
» Vectors
» Software Vector Numbers
» VDUXV
VDU ExtensionVector (27)
| Entry | |
|---|---|
| R0 | Byte send to VDU |
| Exit | |
|---|---|
| R0 | Preserved |
| C flag set if byte is to be sent to printer | |
Use
This vector is called when VDU output has been redirected by OS_WriteC destination flag (setting bit 5).
Notes
If bit 5 of the output stream flag (see OS_Byte 3) has been set then characters which would have been sent to the display are routed to this vector instead. Characters sent to other output streams (e.g. *Spool file, printer) are unaffected.
If the C flag is set on return, then the character (unless it is the printer ignore character (see OS_Byte 6)) is sent to the VDU printer stream (if bits 2 and 6 are clear in the output stream flag). This is independent of the setting of bit 3 in the output stream flag.
The PRM is not clear as to whether this can send the byte twice if bit 3 is set (printer enabled). Confused? :-)