FORTRAN 1.0 is an earlier version than documented in the 1976 and 1977 manuals.
One area in which v1.0 differs is in the optional numeric parameter that can
follow the listing device name.

FORT,#CN[x],objFn,srcFn

#CN specifies the console as the listing device. #LP specifies the printer
as the listing device. The device names allowed are the same, however, the
meaning of the optional numeric parameter 'x' is different.

'0': Normal listing is generated (same as no number at all).
'1': Suppress the source, only the symbol table for each module is listed.
'5': Show the data generated by the compiler for each source line. 

Any other digit displays '?' like it wants additional input to continue.
I have not yet investigated what the expected input is.