I_ N_ T_ E_ R_ N_ A_ L_   F_ U_ N_ C_ T_ I_ O_ N_ S_

  FABS(E1). . . . . . . . Returns the absolute value of the argument
  FADC(N)*. . . . . .Reads A/D converter channel N (LAB/8e or PDP12)
  FATN(A) . . . . . .Computes the arctangent of A, result in radians
  FBLK(). . . . . . . . .OS/8 block number of the current input file
  FBUF(I,V)*. . . . . . . .Display buffer storage (single-precision)
  FCOM(I,V) . . . . . . . .Extended data storage in Fields 2 and 4-7
  FCOS(A) . . . . . . . . Computes the cosine of A (A is in radians)
  FCTR(N)*. . . . . . . . Reads a frequency counter using timebase N
  FDAC(N,V)*. . . . . . .Sets D/A converter channel N to the value V
  FDAY(MONTH*256+DAY*8+YEAR-78) . . .Reads/Sets the OS/8 system date
  FDIN(B1,B2,...,Bn)*. . Reads selected bits from the input register
  FDVM(N,R)*. . . . . .Reads a digital voltmeter, channel N, range R
  FEXP(E1). . . . . . . . . Base 'e' exponential function  |E1|<1420/
  FIN() . . . . . .Reads a single character, returns the ASCII value
  FIND(C) . . . .Searches for code C, returning C if found, 0/ if EOF
  FITR(E1). . . . . . . . . Returns the integer part of the argument
  FJOY(I)*. . . . .Places the cursor (joystick) coordinates in XJ,YJ
  FLEN(I) . . . . File length: I='0/' for 'O'utput, I='1' for 'I'nput
  FLOG(E1). . . . . . .Natural logarithm of the absolute value of E1
  FLS()*. . . . .Returns unsigned value of the Left Switches (PDP12)
  FMIN(A,B)/FMAX(A,B) . . . .Returns the minimum or maximum argument
  FMQ(N). . . . . Displays the lower 12 bits of N in the MQ register
  FOUT(C) . . . . . . .Outputs character code C, returns the value 0/
  FRA(I,V). . . . . . Reads or writes in a binary file at location I
  FRAC(E1). . . . . . . .Returns the fractional part of the argument
  FRAN(). . . . . . . . . . Pseudo-random number function, range 0/-1
  FSAM(N) . . . . . .Samples N channels and stores results in buffer
  FSGN(E1). . . . . .Returns -1,0/,+1 for E1 negative, zero, positive
  FSIN(A) . . . . . . . . . Computes the sine of A (A is in radians)
  FSQT(E1). . . . . . . .Finds the square root using Newton's method
  FSR()/FRS() . . . .Reads the Switch Register or the Right Switches
  FSS(N)* . . . . . . . . . .Tests Sense Switch N: -1 = OFF, +1 = ON
  FTIM(N)*. . . . . . Reads, sets or clears the elapsed time counter
  FTRG(N)*. . . . . . . .Returns status and clears Schmitt trigger N
  FTRM() . . . . . . . . . . . . . Returns the last input terminator
  FXL(N)* . . . . .Tests external level N (PDP12) returning -1 or +1
  And others. . . . .There are a total of 36 possible function names

     Functions indicated by a * are not available in all versions
     The functions FBLK & FLEN are useful in filename expressions
     FIN, FOUT, FIND and FTRM use decimal ASCII codes - see below



      D_ E_ C_ I_ M_ A_ L_   A_ S_ C_ I_ I_   C_ H_ A_ R_ A_ C_ T_ E_ R_   C_ O_ D_ E_ S_

    Code Character        Code Char         Code Char   Code Char

    128  Ctrl/@ (leader/  152  Ctrl/X       176   0/     20/1   I
         trailer-ignored) 153  Ctrl/Y       177   1     20/2   J
    129  Ctrl/A           154  Ctrl/Z (EOF) 178   2     20/3   K
    130/  Ctrl/B           155  ESCAPE  or   179   3     20/4   L
    131  Ctrl/C (OS/8)         Ctrl/[       180   4     20/5   M
    132  Ctrl/D           156  Ctrl/\       181   5     20/6   N
    133  Ctrl/E           157  Ctrl/]       182   6     20/7   O
    134  Ctrl/F (break)   158  Ctrl/^       183   7     20/8   P
    135  Ctrl/G (BELL)    159  Ctrl/<-       184   8     20/9   Q
    136  Ctrl/H (backsp)  160/  SPACE        185   9     210/   R
    137  Ctrl/I (TAB)     161   !           186   :     211   S
    138  LINEFEED         162   "           187   ;     212   T
    139  Ctrl/K (lineup)  163   #           188   <     213   U
    140/  FORMFEED         164   $           189   =     214   V
    141  RETURN           165   %           190/   >     215   W
    142  Ctrl/N           166   &           191   ?     216   X
    143  Ctrl/O           167   ' (apost)   192   @     217   Y
    144  Ctrl/P           168   (           193   A     218   Z
    145  Ctrl/Q (X-ON)    169   )           194   B     219   [
    146  Ctrl/R           170/   *           195   C     220/   \
    147  Ctrl/S (X-OFF)   171   +           196   D     221   ]
    148  Ctrl/T           172   , (comma)   197   E     222  ^ or ^
    149  Ctrl/U           173   - (minus)   198   F     223  <- or _
    150/  Ctrl/V           174   . (period)  199   G     253  ALTMODE
    151  Ctrl/W           175   /           20/0/   H     255  RUBOUT

    Codes 224-250/ are lower case letters.  Codes 0/0/0/-127 are similar
    to codes 128-255 except that the parity bit has been eliminated.
    Many keyboards use 'Shift/K/L/M/N/O' for '[','\',']','^' and '<-'
    A single quote before a character indicates the-value-of: 'A=193
    Use 'Ctrl/@' to page the TV display to avoid getting error 12.40

    To erase the screen on a Tektronix terminal: S FOUT(27) FOUT(12)
    To make a copy: S FOUT(27) FOUT(23).  Note:  FOUT(27) = 'ESCAPE'
    To make bold letters on a Centronics printer: T :FOUT(14) "text"
    To set 'Hold Screen' mode (VT50/ terminals):  S FOUT(27) FOUT(91)
    To rubout the last character on the PDP12/LAB8e display FOUT(92)