pdp BASIC-11 query

I'm posting this on behalf of someone not on the list. I didn't want to just open them up to tons of replies, so figured I'd just post it for him and relay any responses back. Can anyone solve his issue? He wrote.. I'm trying to get some code that was written in 1977 working again. I've gotten a PDP-11 emulator working but the version of BASIC that is on it doesn't know the 'FILE #1="DNG1' command. I've been digging through BASIC manuals for BASIC-11 and BASIC-Plus but so far they either don't have an file reading or their file reading commands don't match that syntax. Googling has led me to a few other versions of BASIC that were on the PDP-11 but I can't find manuals for them. Can you point me in the right direction? (The full code is here; https://d2sx9mrt4zumaq.cloudfront.net/wp-content/uploads/2014/04/DND1_Comple te.pdf) (And it is part of this contest; https://www.shroudoftheavatar.com/?p=39149) --- 00010 LET J4=1 00030 PRINT 00100 BASE 0 00110 LET X=0 00120 LET J=0 00130 LET K=0 00140 X1=0 00150 LET X3=0 00160 LET J9=RND(CLK(J9)) 00170 DIM C(7),C$(7),W(100),D(50,50),P(100),I$(100),B(100,6),B$(100) 00180 DIM E(100),F(100),X5(100),X6(100),X2(100),X4(100) 00190 LET G=INT(RND(0)*24+2) 00200 LET H=INT(RND(0)*24+2) 00210 FILE #1="DNG1" 00220 FILE #2="DNG2",#3="DNG3",#4="DNG4",#5="DNG5",#6="DNG6" 00230 RESTORE #4 00240 FILE #7="GMSTR" 00245 RESTORE #7 00250 RESTORE #1 00260 RESTORE #2 00261 RESTORE #3 00262 RESTORE #4 00263 RESTORE #5 00264 RESTORE #6