On Thu, 10 Nov 2016, Noel Chiappa wrote:
  BTW, I noticed a couple of places in DTF.MAC where
error checking code was
 commented out, e.g.:
  ;EHLT4:       XX              ;HALT WITH BLK#IN LIGHTS, CONTINUE
  ;     MOV     #257.,R0        ;TO FIND DATA WORD POSITION
  ;     ADD     TOG1,R0         ;DETERMINE WHICH WORD IS WRONG
  ;EHLT5:       XX              ;HALT WITH #OF WORD IN LIGHTS. 0=REV. CHKSUM
  ;     MOV     @TCDT,R0        ;CONTINUE TO FETCH BAD WORD
  ;EHLT6:       XX              ;HALT WITH BAD DATA IN LIGHTS. CONTINUE
 Maybe it would be useful to un-comment them? 
No, this is the old code to display the error words in the front-panel
display. Instead, my code (that follows the commented one) converts the
words to ASCII octal representation and displays the appropriate error
message on the console.
Christian