The current Comtal driver uses each 8 bit image as an independent device
with all on a common controller. This is a good concept for an image plane
can be individually ALLocated to a user and RSX-11M protects him from unwanted
manipulation by others, or an image may be used by several tasks if no
ALLOCATE command is used. The other addressable memories
also have independent unit numbers.
CD0: - COMTAL IMAGE #1
CD1: - Comtal IMAGE 2
CD2: - " " " 3
CD3: - Comtal GRAPHICS 1
CD4: - Comtal GRAPHICS 2
CD5: - Comtal GRAPHICS 3
CD6: - Comtal GRAPHICS 4
CD7: - Comtal Function memory 1
CD10: - Comtal Function memory 2
CD11: - Comtal Function memory 3
CD12: - Comtal Programmable Target as FM #4
CD13: - Comtal GREEN memory
CD14: - Comtal RED memory
CD15: - Comtal BLUE memory
CD16: - SPECIAL functions unit
This assignment is somewhat arbitrary but goes a long way towards making
individual devices appear as individually addressable items and therefore
protectable, ie color table. Also in the context of the program IMG the
Comtal key board names for images is the same as for the IMG program.
It would even be better if the graphics memories could have their own device
names such as GR1:, GR4:, and the function memories have names FM1:, but
this appears to be a more complex issue because the device drivers are called
by these first 2 characters, -------- but wait we could give LOGICAL device
names to cd3: as GR1: using the ASN so the user could use
these funny names and yet get CD4: when using GR2: ------- horray!!!!!
Now to go do it !!!!!!!!!!!!!!!!
issue the following ASN cmds either local to your terminal at sign on
or globally in the startup commnad file . ASN CD:=IM1:/GBL
CD0:=IM1: - COMTAL IMAGE #1
CD1:=IM2: - Comtal IMAGE 2
CD2:=IM3: - " " " 3
CD3:=GR1: - Comtal GRAPHICS 1
CD4: GR2: - Comtal GRAPHICS 2
CD5: GR3: - Comtal GRAPHICS 3
CD6: GR4: - Comtal GRAPHICS 4
CD7: FM1: - Comtal Function memory 1
CD10: FM2: - Comtal Function memory 2
CD11: FM3: - Comtal Function memory 3
CD12: CU: for CURSOR - Comtal Programable Target
CD13: GR: for GREEN - Comtal GREEN memory
CD14: RE: for RED - Comtal RED memory
CD15: BL: for BLUE - Comtal BLUE memory
CD16: - SPECIAL functions unit
Now we have 13 special units that can be addressed as standard memory types
and can be moved to other types of image display gear regardless how they
are addressed or configured hardware-wise, ie graphics could be in a totally
indepentednt unit made by a different manufacturer !
The generic names used in the above will keep devices functonally seperate
and easier to remember and also have name similar to the swithches used in
th task SHO-controls comtal display output.