To use the old PASCAL compiler, use COMPILE class commands such as
"EXECUTE FOO.PAS".

To use the new Hedricks Pascal, add the switches "/PROC SYS:PASC/LINK":
"EXECUTE FOO.PAS/PROC SYS:PASC/LINK".

For more information and pointers to further documentation, say
"READ PASCAL", or (from a non-display) "TYPE PASCAL.PN[UP,DOC]".