DECUS C combined with RT-11 v5.3

I have now managed to make an RX33 boot disk image from RT-11 v5.3 and Decus C.  However, I did have to remove some extra files from the original boot disk to make more space.  These are the extra files that I removed:

RT11BL.SYS, RT11PI.SYS, RT11AI.SYS, RT11FB.SYS, RT11SJ.SYS
STARTA.COM, STARTS.COM, STARTF.COM

I guessed that since I'm using the "XM" edition of RT-11, then I would not need those files.  Next, I copied over the DECUS C files, like this:

With CCDSK1.DSK in drive DK1:

CREATE sy:cdisk.dsk/allocate:1500
MOUNT ld0: sy:cdisk.dsk
ASSIGN ld0: c:
INITIALIZE c:
[LD0:/Initialize; Are you sure?] YES
COPY dk1:*.* c:

...now put disk CCXDSK.DSK in drive DK1:

If you've restarted the emulator to change disks, use the next two lines:
MOUNT ld0: sy:cdisk.dsk
ASSIGN ld0: c:

COPY dk1:*.* c:
@C:CCSET.EIS
@C:CCXASM.V53

Append these lines to your "STARTX.COM" command file (which runs when RT-11 starts):

MOUNT ld0: sy:cdisk.dsk
ASSIGN ld0: c:
@C:CCXASM.V53

Then restart... Finally, to compile a C program, do this:

CC
[CC>] hello.c/A
LINK sy:hello.obj,c:suport.obj,c:clib.obj

Don't forget that this is an old dialect of C, mainly as described by K&R.  So you'll have to stick to the original K&R syntax.  Right, next comes the fun stuff.

Making an RT-11 v5.3 disk image

I realised that if I could get a floppy disk that booted into RT-11 v5.3, then I might be able to add the DECUS C compiler and have a boot disk and C compiler. This is the procedure I used to make my first RT-11 v5.3 boot disk.

Using SIMH, boot into RT-11 v5.3, making sure that you have blank RX33 disk image attached as DK1:. Then use these RT-11 commands to copy the files to the floppy disk image:

COPY/SYS SY:*.SYS DK1:*.SYS
COPY SY:VBGEXE.SAV DK1:
COPY SY:DIR.SAV DK1:
COPY SY:BUP.SAV DK1:
COPY SY:DUP.SAV DK1:
COPY SY:IND.SAV DK1:
COPY SY:LINK.SAV DK1:
COPY SY:KEX.SAV DK1:
COPY SY:PIP.SAV DK1:
COPY SY:V5USER.TXT DK1:
COPY SY:STARTX.COM DK1:
COPY SY:UCL.* DK1:
CLOSE

Then, shut down SIMH. We'll next use PUTR to make the RX33 disk image bootable (this assumes that you have called the image rx33.dsk and that it is in the same folder as PUTR):

MOUNT a: rx33.dsk /rx33 /rt11
BOOT a:
     RT11XM
     DUX
DISMOUNT a:

That's it. The RX33 image should now be bootable. Try it out in SIMH to make sure.