Typically you will want to install the tool change macro into your machine so that it can be used in MDI or from any program and it will always be memory resident. Some use G116, some use G111. You will need to go to your G/M code macro page and set the G111/G116 to OTCHK. Then you will need to register the following library program: (TOOL.LIB) OTCHK ( SET GCODE PARAM. G111 TO OTCHK ) ( AT TOOL CHANGE KEY IN G111 T= TOOL NO. Q = NEXT TOOL EX: G111 T1 Q2) IF [ VTLCN EQ PT ]NST1 (ACTIVE TOOL) IF [ VTLNN EQ PT ]NRT1 (NEXT TOOL) IF [ VTLNN EQ 0 ]NOT1 (NEXT TOOL) M64 NOT1 T=PT NRT1 M06 NST1 IF [ PQ EQ EMPTY ]NEND (IF READY TOOL EMPTY/JUMP ) IF [ VTLNN EQ PQ ]NEND (IF PREP TOOL IS AT NEXT TOOL POS./JUMP) IF [ VTLNN EQ 0 ]NTT1 (IF NEXT TOOL HAS NO VALUE) M64 (NEXT TOOL POT RETURN) NTT1 T=PQ M356 (NEXT POT ADVANCE) NEND G56 H=VTLCN D=VTLCN RTS PQ DEF: WHEN P IS ATTACHED TO A LETTER IT BECOMES READABLE Once registered, it will be available to all programs and even MDI upon power up. This will save you lots of headaches and errors/alarms by making your tool change macro "intelligent". Best regards,

Your problem is probably that you tried to change spindle modes with your G96 still active. You cannot change modes if G138, G96, Nose comp, Lap cycle, M110, etc. are active. They need to be cancelled before attempting to switch modes. Best regards,