/ GCLEAR, GSTART, GSTOP /
 LAP
 ENTRY GCLEA
 ENTRY GSTAR
 ENTRY GSTOP
GXBUF, COMMN 6200
 OPDEF DPLA 6150
 OPDEF DPGO 6151
 OPDEF DPSM 6152
 OPDEF DPCL 6156
 OPDEF CDFGX 6211
 ABSYM AIR1 11
 ABSYM CTR 177
 OPDEF ANDI 0400
 OPDEF TADI 1400
 OPDEF ISZI 2400
 OPDEF DCAI 3400

GCLEA, BLOCK 2
 CLA CMA /-1/
 TAD ZGXBU
 DCA AIR1
 TAD (-6200
 DCA CTR
 CDFGX
GCLOOP, DCAI AIR1
 ISZ CTR
 JMP GCLOOP
 RETRN GCLEA

GSTAR, BLOCK 2
GSWAIT, DPCL
 JMP GSWAIT
 TAD ZGXBU
 DPLA
 NOP
 NOP
 TAD (0012
 DPGO
 RETRN GSTAR

GSTOP, BLOCK 2
 DPSM
 RETRN GSTOP

ZGXBU, GXBUF

 END