MACRO-10

MACRO-10is anassembly languagewith extensivemacrofacilities forDEC'sPDP-10-basedMainframe computersystems, theDECsystem-10and theDECSYSTEM-20.MACRO-10 is implemented as atwo-pass assembler.

Programming examples

A simple "Hello, world!"program in MACRO-10 assembler, to run underTOPS-10,adapted from a specimen in a large collection of "Hello World" programs in various languages:

TITLEHELLOWORLD
;'Hello world' in MACRO-10 for TOPS-10
SEARCHUUOSYM;Make UUO symbol names available

LAB:ASCIZ/Hello,world!
/;NUL-terminated ASCII string with CRLF

START:RESET;Initialise job to clean runtime state
OUTPUT:OUTSTRLAB;Output string starting at LAB:
MONRT.;Return to monitor
JRSTOUTPUT;Restart at OUTPUT: if user CONTINUEs job
ENDSTART;End assembly, set program start address

If this program is saved in the fileHELLO.MAC,it can be assembled, linked and run like this (the TOPS-10 system prompt is the.at the start of lines):

.COMPILEHELLO.MAC/DLIST
MACRO:HELLO

EXIT

.LOADHELLO
LINK:Loading

EXIT

.SAVE
HELLOsaved

.RUN

Hello,world!

.

The assembly listing file generated by the/DLIST(Disk LISTing) option to theCOMPILEcommand:

HELLOWORLDMACRO%53B(1247)17:297-Apr-:9Page1
HELLOMAC7-Apr-:917:29

TITLEHELLOWORLD
;'Hello world' in MACRO-10 for TOPS-10
SEARCHUUOSYM;Make UUO symbol names available

000000'110145154154157LAB:ASCIZ/Hello,world!
000001'054040167157162
000002'154144041015012/;NUL-terminated ASCII string with CRLF
000003'000000000000000

000004'04700000000000START:RESET;Initialise job to clean runtime state
000005'05103000000000'OUTPUT:OUTSTRLAB;Output string starting at LAB:
000006'04701000000012MONRT.;Return to monitor
000007'25400000000005'JRSTOUTPUT;Restart at OUTPUT: if user CONTINUEs job
000004'ENDSTART;End assembly, set program start address

NOERRORSDETECTED

PROGRAMBREAKIS000010
CPUTIMEUSED58:25.100

36PCOREUSED

HELLOWORLDMACRO%53B(1247)17:297-Apr-:9PageS-1
HELLOMAC7-Apr-:917:29SYMBOLTABLE

LAB000000'
MONRT.047040000012
OUTPUT000005'
OUTSTR051140000000
RESET047000000000
START000004'

The date ":9" is aYear 2000 problem. A more complex MACRO-10 example program, which renders one version of the99 Bottles of Beersong, may be examined at the "99 Bottles of Beer" web site.

For larger bodies of code, much of the MACRO-10 code for the TOPS-10 and TOPS-20 systems is available in the Trailing Edge PDP-10 tape archives.

External links

• DECsystem-10 Macro Assembler Reference Manual(PDF).Maynard, Massachusetts: Digital Equipment Corporation. April 1978.Retrieved2010-07-08.
• Singer, Michael (1978).Introduction to DECsystem-10 Assembler Language Programming.New York: John Wiley & Sons. p. 145.ISBN0-471-03458-4.
• Gorin, Ralph E (1981).Introduction to DECSYSTEM-20 Assembly Language Programming.Bedford, Massachusetts: Digital Press. p. 539.ISBN0-932376-12-6.