Now we can write a short program to test our macros.
ABSTEST2 START 0 WAITPSW DC X'0000000000',AL3(BEGIN) * * ORG ABSTEST2+2048 * BEGIN BALR R12,0 SET BASE REGISTER USING *,R12 * LA R13,SAVEA FIRST SAVE AREA
We start by loading a PSW at location zero. Our PSW will start executing at lable BEGIN. Because the lower byes in memory are used for communication between the CPU and the operating system software we need to load our executable program in higher memory. Using the ORG statement we will being our program at 2K (2048).
We begin by establishing register 12 as a base register and placing our initial save area address into register 13.
@PRINT 'HELLO, WORLD' PRINT "HELLO WORLD"
@PRINT DASH,LEN=L'DASH PRINT A LINE OF DASHES
*
LOOP DS 0H
@CARD INBUF READ A CARD
LTR R15,R15 CHECK FOR GOOD READ
BNZ LOOPEND
@PRINT INBUF,LEN=L'INBUF PRINT THE CARD
B LOOP LOOP BACK FOR ANOTHER CARD
*
*
LOOPEND DS 0H
@PRINT DASH,LEN=L'DASH PRINT A LINE OF DASHES
@PRINT ' ' PRINT BLANK
@PRINT ' ' LINES
*
*
L R5,=A(BEGIN)
@DUMP (R5),128 DUMP SOME STORAGE
*
LPSW DONE
Now we use our @CARD macro to read from the card reader. We check the return code in register 15 to see if a card was read. If not we branch out of the loop. If a card was read we print using the @PRINT macro and then loop back an attempt to read another card.
After reading the last card we print a line of dashes an two blank lines. We then test the @DUMP macro by dumping 128 bytes of our executable program. We then load a wait state PSW to end execution.
@PRINT GEN=YES @CARD GEN=YES @DUMP GEN=YES @ERR , @REGS , * ******************************************************************* * DASH DC C'------------------------------------------------- * * DS 0D DONE DC X'0002000000',X'99FACE' * SAVEA DS 18F * INBUF DS CL80 * END ,
Now we include the GEN=YES forms of our @CARD, @PRINT and @DUMP macros to generate the subroutine code. We also use the @ERR and @REGS macros to define our error codes and registers.
Our data areas include a line of dashes, a PSW with the wait bit set, a save area and an input buffer.
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